Will Smith grew so enamored of his canine co-star, Abbey, that he tried to adopt her when filming was finished, but the dog's trainer could not be persuaded to give her up.

When Robert Neville sees the mannequin he calls Fred outside on the street, it looks like the mannequin moves its head a little. During that scene, a mime replaced the mannequin to try and play with people's minds when they watched that scene.

When he was in pre-production on this film, director Francis Lawrence found himself watching The Pianist (2002) with the sound off in order to not disturb his sleeping baby, and he found the quiet effect was extremely moving. He then made stark silence, with limited ambient effects or musical cues, a major part of this film's process.

The screams and unearthly sounds of the infected creatures in the film are by Mike Patton, vocalist in Faith No More, "Fantomas" and Mr. Bungle.

Will Smith talked to former prisoners to get an understanding of what it's like to be totally alone. The prisoners told Smith the key to surviving solitary confinement is creating a rigid schedule.

Warner Bros. initially opposed filming in New York City, because of the costs and logistical challenges. However, Michael Tadross, a veteran New York City production manager, got the city to approve closing the Grand Central viaduct, several blocks of Fifth Avenue and Washington Square Park, albeit at night and on weekends, between September 2006 and April 2007.

While doing a press conference in Japan for the release of the movie, Will Smith accidentally revealed the ending to a collection of entertainment reporters. Warner Bros. asked the reporters and all those present to withhold the ending, and the reporters all obliged without any pay-off or consideration.

The trainer put a piece of tape on Abbey's paw to make her limp.

The studio spent an estimated five million dollars for a six-night shoot in New York City, involving the Brooklyn Bridge. To film in this location, the producers needed the approval of as many as fourteen government agencies. The shooting required a crew of 250, plus 1,000 extras, including 160 National Guard troops in full combat gear.

All of the paintings in Dr. Neville's house were provided by the Museum of Modern Art in New York City.

While shooting under the Brooklyn Bridge at the end of January, it got as cold as seven degrees Fahrenheit. To boost everyone's spirits one night, Will Smith came out and sang his hit song "Summertime" (1991).

The film was green-lit without a script.

Will Smith met with scientists from the Centers for Disease Control to learn how to use all of the equipment properly.

The movie's animal trainer found Abbey in a kennel. She had the right look, but had never been trained. He only had a few weeks to get her up to speed.

Plants were transported via trucks from Florida to dress up the city streets as if weeds had overtaken them.

Before they started filming, Will Smith went on "dates" with Abbey (the dog who plays Sam) so he could get to know her better.

Most of the movie has no underlying score. The score was used minimally to highlight Neville's solitude.

In one scene in the deserted street, a billboard can be seen with a large Batman and Superman logo superimposed over each other, and the date "5-15-10." This is an in-joke at the expense of screenwriter Akiva Goldsman. Goldsman did script rewrites for a "Batman Versus Superman" project in 2002. This was just one of the countless attempts to revive the Superman franchise that culminated in the release of Superman Returns (2006). It would not be until 2016 that Superman and Batman would share the silver screen together in Batman v Superman: Dawn of Justice (2016). Will Smith later played Deadshot in Suicide Squad (2016), which takes place in the DC Extended Universe of Batman v Superman: Dawn of Justice (2016).

Some of the mannequins in the video store were played by real people. If you look closely in the scene, you can see them move.

Warner Bros. Pictures has owned the rights to the book since the 1970s. The studio first attempted adapting it as The Omega Man (1971) with Boris Sagal directing, and Charlton Heston starring, then as " I Am Legend' with Ridley Scott and Arnold Schwarzenegger starring, which fell through when the production went over-budget. And then in 2002, Michael Bay was set to direct Will Smith, but they decided to make Bad Boys II (2003) instead.

The scenes at the Brooklyn Bridge involved over 1,000 extras and various military vehicles and aircraft.

At the New York premiere, Will Smith apologized for the disruption shooting of the movie had caused to the city residents. He said, "I would like to issue a public apology to the citizens of New York. There were a couple of streets we had to close off during the filming of I Am Legend (2007). I am very sorry. People were kind of upset with me."

Although the creatures are referred to as "Dark Seekers," during the film, if watched with the subtitles on (DVD), they are called "Hemocytes."

Will Smith said that closing New York City streets to film, meant he got a lot of "middle fingers."

Much of this film was shot on location in New York City's Washington Square Park, during fall and winter 2006-2007, causing holiday decorations to be taken down, and replaced tumultuously for over three months.

The noise from the special effects explosions, used in the scenes along the East River, interrupted voice recording on the Nickelodeon children's show Wonder Pets! (2005), which had its production offices one block from where the shooting of I Am Legend (2007) took place.

The filmmakers couldn't close all the streets at once, so each weekend, they'd film Will Smith driving on a different corner. People on the street hid, and took cellphone videos of Smith, as he drove by.

When shown in IMAX theaters, this film played without any previews, save for the six-minute opening bank heist sequence from The Dark Knight (2008).

According to Akiva Goldsman, there were plans to produce a follow-up film, with scripts even being written around a prequel and sequel. One prequel involved the outbreak occurring during the Thanksgiving Day parade in New York City, while another focused on the human population becoming low. The latter prequel featured a trip to Washington, D.C., and an infected elephant escaping from the zoo. However, the project was effectively shelved.

In the film, Will Smith's character holds up a CD, calling it "the best album ever made." The album is Bob Marley's "Legend," which is a greatest hits compilation that was released after Marley's death.

Will Smith's daughter, Willow Smith, plays his daughter in the movie.

The exterior of Robert Neville's townhouse was shot on location in Washington Square, but the interior of this townhouse was filmed on a set in Brooklyn.

When Neville brings Sam back to his lab and gently sets the dog on the operating table, nearby trainers cued the dog to "play dead" and keep her head down. The actor was well-rehearsed in handling the dog. For a shot when Sam tries to bite Neville, a chew toy was placed near the actor's shirt and the dog was cued to "get it." The toy and the trainer were in the scene but removed in post-production. The syringe he uses was a retractable prop and the dog was never injected. The dog's red eyes and veins were a digital effect.

Before it was finally green-lit with Will Smith as the lead, and Francis Lawrence directing, the closest the project came to being made was in early 1998, when Warner Bros. gave an initial "OK" for a version starring Arnold Schwarzenegger, with Ridley Scott directing. The studio's art direction and special effects workers had even begun working on a design for the apocalyptic mutant creatures. However, some high-profile big-budget failures for Warner Bros., and the huge (for that time) initial budget of 125 million dollars, led to the project being put into turnaround. If the film had been made from Mark Protosevich's original screenplay, it would have differed from the 2007 version in three major ways: it was to be set in the Bay Area of California, it would have been more of an action film, and less of a drama, and it would have been filmed with the intent of being R-rated, which would have possibly drawn in fewer viewers.

In the book by Richard Matheson, people who died of the disease return to life as vampires, retaining their human appearance. Like traditional vampires, they dislike garlic and mirrors, hunt the living, and die from a stake through the heart.

Guillermo del Toro, Will Smith's first choice, turned down the offer to direct this film so he could make Hellboy II: The Golden Army (2008).

Air cannons and hydraulic rigs were used to make Neville's house shake during the explosions.

Foreshadowing: Neville captures an infected female with a snare trap, and the Alpha of the pack leaves the dark to glare at Neville before walking back into the dark. Neville takes it as a sign that they've lost their self-preservation skills. The Alpha later shows up, having caught Neville in the exact same type of snare trap he built with a pack of dogs, hinting that the infected are intelligent, and that the Alpha wants the girl back.

The "Darkseekers" were created using animation with actors in motion capture suits. They tried live actors, but Akiva Goldsman said it looked "like Attack of the Angry Mimes."

Above Neville's television is a replica of Vincent van Gogh's "Starry Night," a painting showing the violence and chaos of a night sky.

The original plan was to have the infected people be played by real people wearing extensive make-up and prostetics, but the first tests results made them look more like "angry mimes," according to the crew. The choice was then made to use computer generated imagery (CGI) to depict the creatures instead.

The film takes place in 2009 and 2012.

In the beginning, while the Doctor is being interviewed about the cure for cancer, there is a news ticker at the bottom of the screen with the headline, "Shaquille O'Neal to announce his retirement at the end of 2010 season."

Nicolas Cage was considered for the role of Robert Neville back in 1998, along with Rob Bowman to direct. Bowman eventually moved on to direct The X Files (1998).

Will Smith called the head of DreamWorks to ask to use Shrek (2001) in the movie.

It was too difficult to shut down Times Square, so the hunting scene was shot on a soundstage.

The dog's injuries were created using prop blood made of a nontoxic petroleum jelly/corn syrup mixture.

Sam and several "infected" dogs get into a fight. A shot of Sam was filmed for reference, and then the fight was computer-generated.

Tom Cruise, Nicolas Cage, Michael Douglas, Mel Gibson, Daniel Day-Lewis, and Ted Levine were considered to star over the years the film was in development.

It took a team of around 300 people fourteen months to create all the computer-generated creatures.

The movie's infected dogs were based on Mexican hairless dogs (known as Xolos) that the trainer owned.

Will Smith left the production for a couple of days to attend Tom Cruise's wedding to Katie Holmes in Rome, Italy.

Before the helicopter crash in the flashback, Marley gives Sam (when she was a puppy) to Neville saying, "Sam you protect Daddy", foreshadowing when Sam actually saves him from infected dogs.

The Bob Marley song, "Three Little Birds," was previously used in another Will Smith film, Shark Tale (2004).

Steven Spielberg visited the set one day. It made everyone very nervous. Spielberg's first movie, Duel (1971), was written by Richard Matheson, the author of I Am Legend.

In 1999, in an early point in development, Tim Burton was interested in the project.

Warner Bros. gained the rights to the novel by Richard Matheson in the 1970s and produced a version of it, called The Omega Man (1971), in 1971. Previous to that, Associated Producers did an adaptation in 1964 called The Last Man on Earth (1964) with Vincent Price, shot in Italy and directed by Italian Ubaldo Ragona and American Sidney Salkow. Although Matheson did not contribute to the screenplay of the 1964 film, which took a critical drubbing, he did contribute to the screenplay for this film.

When Neville carries the injured Sam after the fight, trainers placed her in a "down/stay" position and cued her to keep her head down as the actor lifted her and placed her in the car.

Release prints were delivered to theaters with the fake title "Blood Allies."

Kurt Russell was once considered to star in the late 1990s, but after the failure of Soldier (1998), he was no longer considered.

Francis Lawrence said, "There is... an AIDS metaphor here... in terms of dealing with the infected. They're not dead... they're not vampires... they have a chronic disease."

When Sam runs on a treadmill, the dog was well-rehearsed to run on the treadmill. Trainers got her accustomed to a slow walk and gradually worked their way to a run. The dog was attached to a safety rope held by a trainer, but she was so comfortable with the action that the trainer never needed to use it. The dog was rewarded with treats.

In the beginning of the film, Neville is driving a Ford Mustang. This could be a reference to the 1971 version The Omega Man (1971), in which Neville also drove a Mustang.

Dr. Krippin is named after the first murderer caught as a result of telecommunications, to create a sense of sinister foreboding.

Anna was written to be American, but Alice Braga was the only person producers wanted for the role.

When Neville gives Sam a bath. The dog was accustomed to getting baths and the water was comfortably warm. The shampoo was a no-tears formula and a traction mat lined the bottom of the tub. The dog was given treats and was thoroughly rinsed and dried between takes.

In flashback scenes, Sam is seen as a puppy. For these scenes, trainers instructed the actors on how to perform the mild action, mostly holding the puppy in their arms or laps. The scene with the puppy in the moving vehicle was filmed on an indoor stage against a green screen, and a trainer was hiding in the backseat. The vehicle never actually moved; crew members rocked the vehicle to make it appear to move, and the moving background was added in later. The puppy was accustomed to being held and was unfazed by helicopter noises. Between takes, she was placed in a heated blanket to keep her warm and relaxed. The helicopter explosion was computer-generated imagery (CGI).

Sam is on the wing of an aircraft while Neville drives golf balls. This scene was filmed on an actual airplane with especially large wings. The trainer walked the dog up custom-made stairs and put her in a "down/stay" position on a platform with special traction on top of the wing. The trainer hid in a nearby box where he maintained the dog's eye contact and cued it to stay. Several trainers surrounded the area as a precaution. The trainer walked the dog down the stairs immediately after filming.

Although they don't share a scene, this is the first movie together for Emma Thompson and Will Smith. They would meet again in Men in Black 3 (2012).

Creature designer Patrick Tatopoulos also created the aliens for Will Smith's Independence Day (1996). His studio made 3-D sculptures of the designs, which were used as a reference for computer animation.

All the artwork in Robert Neville's house has been "rescued" from New York City's various museums. They used replicas of famous paintings for the movie.

Neville wears a Belstaff Trialmaster "Legend" jacket.

When Sam is seen in a moving vehicle, a foam mat covered the car seat for traction, and the dog was tethered to the seat with a waist tie, which was held by a trainer hiding in the backseat. The backseat trainer gave the dog commands, and a trainer just outside the car door occasionally held food out to get the dog to stick her head out. A stunt car was used for the part of the scene in which Neville drives erratically. High-speed chases were filmed in separate shots without the dog -- she was never actually in a high-speed chase or jolted around in a sudden stop. For shots in which the car spins around, crew members propped the special car up onto rotating dollies and manually spun it for the short take. The dog, who seemed to enjoy the movement, was secured in the car and held by the trainer. For scenes in which the car simply drives down the street, the actor drove slowly and the dog was secured by a waist line attached to a harness and leash held by a backseat trainer.

It is highly plausible that, within the story, the timecoded copies of the NBC Today show, and anything else he would have watched on broadcast television, would have been taken from the NBC base at 30 Rockefeller Plaza (a.k.a. 30 Rock).

Nine-year-old Charlie Tahan had never been in a movie before 2007 - but by the end of that year, he'd done three.

Production designer Naomi Shohan had previously worked with Francis Lawrence on Constantine (2005).

About ten minutes after the beginning, in a recorded television program, the movie can be seen for a few seconds at the Piazza San Carlo in Turin, Italy, the city of the 2006 Winter Olympic Games.

The rifle used by Will Smith throughout the movie is a Colt Law Enforcement Model 6920 Carbine with a Trijicon ACOG optic (TA31 series), C-MORE free floating rail, ERGO rail covers, and Pentagon MD3R tactical light. According to the Propstore of London, the weapon was modified to fire fully automatic for the film, he also uses a Heckler & Koch Mark 23 with a flat earth (tan) frame as his main sidearm. He is seen with it holstered, but also carries one in the driver's door, most notably to shooting the infected dogs in the middle of the film. There were several identical firing Mark 23s used on-set, as well as rubber versions for stunt work. For most scenes where Will Smith carried the weapon in the holster, a lightweight airsoft Mark 23 (with frame painted tan to match the firing pistols) was used, and a Beretta 92FS, and a Smith & Wesson 5946. The 5946 in the DAO setting is one of three pistols used by the NYPD (the other two being the Glock 19 and the P226 DAO), so it was likely recovered by Neville from an NYPD precinct.

Cameron Monaghan auditioned for the part of Ethan.

The film that Ethan watches is Shrek (2001). Eddie Murphy whom provided the voice of Donkey in that movie had starred opposite Will Smith's wife Jada Pinkett Smith in The Nutty Professor (1996), the same year Will did Independence Day (1996).

Will Smith and Charlie Tahan have both worked in DC related material; Smith played Floyd Lawton aka Deadshot in Suicide Squad (2016) and Tahan played a young Jonathan Crane aka The Scarecrow on Gotham (2014-2019).

There is an alternate ending of the film where Robert Neville (Will Smith) not only survives, but also learns a very valuable lesson. When the monsters are attacking them, the leader stops and then makes a butterfly with his dirty hands on the window. Smith's character then sees a butterfly tattoo on the infected woman that he kidnapped to experiment on. He reunites her with the monsters and the leader passionately rubs heads with her and lets out a very pained roar while crying. Neville learns that the monsters may not be human, but have still retained some human emotions and higher brain functions. He tearfully apologies to the leader, who then orders the rest of the infected people to leave them. Neville then breaks down, sitting and looking at the pictures of earlier test subjects that died during his experiments. He then abandons his research and leaves by car, together with Anna and Ethan, and the vial of blood containing the cure. This idea was completely edited out of the film and a new ending put in, where Neville gives the cure to Anna. He then saves her and Ethan by blowing himself and the monsters up with a grenade. Anna and Ethan subsequently leave for Vermont and find the colony. Many people hated this ending, so a version with the alternate ending was released on limited edition DVD sets & the Blu-Ray version. Many people prefer the alternate ending over the theatrical ending, believing it gives the plot a moral and more meaning to the film's title by having Neville doing something "legendary".

The death of Sam the Dog was voted online as "One of the Saddest Film Scenes of All Time."

In the last scene of the theatrical version, Anna and Ethan are driving through the autumn countryside. This scene was filmed in West Amwell, New Jersey, because in the original filming location, the leaves on the trees had already fallen off.

During the scene where Neville is searching the apartments, there is an article posted on one of the cabinets stating that infected dogs could come out at dusk, leading to a later scene where Neville and Sam are attacked by dogs. This explains why the Alpha does not also attack Neville as the sun had not completely gone down.

In Times Square, there is a billboard for the Justice League: Mortal movie set to open May 10, 2010. Also in the video store, posters for the live action adaptations of Teen Titans and Green Lantern (2011).

There are references to butterflies scattered throughout the movie: the "God Still Loves Us" poster; when Neville was talking to Sam about the mannequin he met in the video store, a butterfly is shown flying near Sam's face for about a second; at the ending, the Dark Seeker makes cracks in the glass that represent a butterfly; Neville hearing "Daddy, its a butterfly!" (a quote from his dead daughter); Anna has a butterfly tattoo on her neck.

All vehicles driven by the main characters are Fords. There is the Ford/Shelby GT500 Mustang that Neville drives in the beginning, the Ford Expedition he drives throughout the film, and the Ford Escape used to depart New York City at the end.

Neville kills himself and the darkseekers with a, M67 High-Explosive Fragmentation hand grenade.