Director Mike Nichols had originally wanted Michelle Pfeiffer to wear a red-hooded sweatshirt for the film's final act. She refused, as she thought it would harm the film's credibility.

Jack Nicholson had been trying to get this film made with his friend, writer Jim Harrison, for twelve years.

In Christopher Plummer's new memoir, he revealed that while filming a scene, he got so into character that he actually slapped Michelle Pfeiffer across the face instead of faking it.

Michelle Pfeiffer adopted a baby girl, became engaged and got married all during the making of this film.

Despite their on-screen relationship, Michelle Pfeiffer and James Spader became friends during the making of this film and were still friends when Pfeiffer's husband, television Producer David E. Kelley, was looking for the male lead for Boston Legal (2004).

Although the film is about a werewolf, that particular word is never mentioned. Instead, the phrase "demon wolf" is used several times.

The scene where Will hunts a deer was filmed day-for-night.

The last horror film in which Jack Nicholson starred.

In the scene when Jack Nicholson realizes that his senses are all incredibly acute, when he is in his office building, there is a voice off camera that says "No. I'm not gonna do it." That line is said by Director Mike Nichols.

When Michelle Pfeiffer expressed interest in playing the part of Laura, Mike Nichols and the film's screenwriters wanted to make the part stronger and more important to the story, as it was basically a "woman in danger" trope in the original script. Some of the ideas considered were making her into an animal rights activist or a doctor, both of which would have given her a connection to Jack Nicholson's character and expanded on her conflict with her rich father. Ultimately, Pfeiffer accepted the role without it being hugely upgraded because she wanted to work with Nicholson and Nichols.

Jack Nicholson had final say about who the choice of the director would be, and in fact one of his choices was Mike Nichols.

Mia Farrow was slated to play Charlotte Randall. Mike Nichols had to fight to let Farrow have the part, due to the film company's hesitancy over her being too controversial at the time (the then current Mia Farrow and Woody Allen trial). She had to take a salary cut but in the long run she had to bow out anyway, due to schedule conflicts.

Stanley Kubrick was considered to direct, but he wasn't interested.

Sharon Stone turned down the female lead.

Jack Nicholson and Michelle Pfeiffer appeared in The Witches of Eastwick (1987).

Prunella Scales filmed her part in four days.

The final collaboration between Mike Nichols and Jack Nicholson.

When Strick was writing the scene where Will attacks a deer, a real deer appeared outside his window as he was writing the death of the deer in the film.

Film debut of Alison Janney as a party guest early on in the film

At the beginning of production, Jack Nicholson told Rick Baker that he was allergic to spirit gum. While he initially didn't believe him, Baker agreed to use a specific medical adhesive on Nicholson which made hand laying the hair on him very difficult as opposed to using spirit gum. One day after he made up James Spader using spirit gum, Baker unintentionally used the same bottle of spirit gum on Nicholson. Baker soon realized what he had done and hoped that Jack wouldn't find out seeing how nothing happened during the application. The next day, Baker was horrified to see that Nicholson wasn't lying as he entered the makeup trailer with large red swells on his face. Nicholson said, "Ricky boy, you used spirit gum, didn't you?" Baker apologized for the confusion and Nicholson stated, "Well, let's just hope it doesn't happen again." Fortunately for everyone, it didn't happen again.

The daughter of Jack Nicholson plays a role as an office worker.

Before Christopher Plummer was cast, Marlon Brando personally called Wick to express interest in the role of Raymond Alden.

Jack Nicholson, Richard Jenkins, and Michelle Pfeiffer appeared in The Witches of Eastwick (1987).

Contrary to popular belief, the entire third act of the film was not re-shot. Only the shot of Will jumping over the bars of the stable Laura locked him in was added when the studio felt a small amount of extra action was needed. The cost of the shot was nearly a million dollars, to which Nichols referred to as: "$700,000 worth of aspirin for the studio."

John Williams was originally attached to compose the music for this film. Soon left the project after the film was delayed, and needed some time off after winning the Oscar for Schindler's List (1993), as he'd been working on Jurassic Park (1993), Schindler's List (1993), and overseeing the Boston Pops Orchestra in Boston.

Randall, the last name of the character Nicholson plays in the film, means "Shield-Wolf."

Producer Douglas Wick says there were two outlooks on the movie: Nichols saw Wolf as a film about loss and death whereas Nicholson, Harrison and Wick saw it as a celebration of oblivion and liberation.

Rick Baker created a small device which allowed Nicholson's ears to move, showing that his senses were changing.

James Spader's stuntman did all his stunts without wires or protection, almost greatly injuring himself during a scene in which Stuart is thrown onto the stone steps of the guest house.

One version of the script ended with a transformed Will being kept on a secluded property with Laura making periodic visits via helicopter.

When Will (Jack Nicholson) meets with Raymond Alden (Christopher Plummer) and his lawyer, on the bookshelves, you can see six Robert Jordan books: One copy of "The Eye of the World", one copy of "The Great Hunt", two copies of "The Dragon Reborn", and two copies of "The Shadow Rising".

The film cast includes two Oscar winners: Jack Nicholson and Christopher Plummer; and four Oscar nominees: Richard Jenkins, Kate Nelligan, Michelle Pfeiffer, and Elaine May.

According to Rick Baker, the makeup for the werewolves were heavily inspired by Jack P. Pierce's work in Werewolf of London (1935). The makeup consists of mostly hair and subtle appliances (pointed ears and a small piece in between the brows). James Spader had more facial appliances than Jack Nicholson because he needed more have more structure on his face in order to have the same power as Nicholson's face.

While schmoozing with other guests at Raymond Alden's (Christopher Plummer's) dinner party, Will (Jack Nicholson) makes reference to "gay senior citizens" as proof that the world has already ended. Christopher Plummer went on to become the oldest actor, at eighty-two, to win an Oscar for Best Actor in a Supporting Role, for portraying a "gay senior citizen" in Beginners (2010).

When asked why she chose to take on the role of Laura, Michelle Pfeiffer simply stated that she: "didn't want to do another accent, didn't want to put on another wig, didn't want to put on another corset," but instead wanted: "to just do something modern day."

In the original script, Will was a lawyer. The character's occupation was changed to publishing because it was felt to be a more fresh approach.

For a while there was some uncertainty as to whether Raymond Alden would either be Laura's brother or her father, with Strick greatly championing the latter suggestion. At the same production meeting between Wick, Nichols and Strick where it was decided that Raymond Alden would be Laura's father, Nichols's assistant interrupted to tell the director that Mick Jagger was waiting outside. Jagger had been greatly interested in the part of Raymond Alden when the role was written as Laura's brother. Since it had been mainly his idea to change the character, Stick was tasked with delivering the news to Jagger that he was no longer right for the role.

According to Strick, the scene in which Will urinates on Stuart's shoes in the men's room symbolized Harrison's flavor of writing, while the scene in which Will talks to himself into the mirror best represented his.

The majority of the film was shot on a soundstage in Los Angeles.

According to Strick and Wick, Nichols felt in part that Wolf was about the death of God, the crumbling of Western civilization and the AIDS epidemic. At the same time, composer Ennio Morricone saw Wolf as a story about a man trapped in a dream.

Jack Nicholson and Michelle Pfeiffer both performed in Batman films, Nicholson in Batman (1989) as The Joker and Pfeiffer in Batman Returns (1992) at Catwoman.

The last Mike Nichols movie edited by Sam O'Steen.

Wesley Strick was brought in to rewrite the script because it was thought that Harrison's screenplay read too much like a novel. According to Strick, the two never met, but he got the feeling that Harrison resented Wick's involvement. Adding to the awkwardness was the fact that star Nicholson had been a close friend of Harrison's for many years. However Nichols was happy to have Strick's participation. Stick found another ally in lead actress Michelle Pfeiffer, whom he had collaborated with when he wrote Batman Returns, one of her most famous films.

Om Puri was enthused and interested to take part in the aging makeup process which he had to endure for his role.

According to screenwriter Wesley Strick, Nichols saw Wolf as an opportunity to reinvent himself as a modern, relevant big-budget movie director.

Producer Douglas Wick described the character of Laura as a lost woman of privilege, while Pfeiffer thought of her as a woman naturally drawn to wounded animals.

Although Michelle Pfeiffer was an early choice, Mike Nichols still had a number of actresses come in to read for the role of Laura.

Bo Welch's production design was meant to symbolize elegance, but also give off a sense that the people who populated the film were lonely, and a little dead inside.

Nichols shot the film with his editor by his side, giving the latter notes throughout.

According to Rick Baker, Nichols was nervous about the more "monster movie" aspects of Wolf, such as Will and Stuart's climax in the finale.

Rick Baker stated that he really enjoyed working with Om Puri. His makeup was a stretch and stipple foundation with a foam latex bald cap and hair pieces to age him 20 years. Puri was equally excited to work with Baker and go through the makeup process.

Dr. Alezais tells Will that on the night he was bitten, March 8th, the moon had been closest to the earth for the first time in 100 years. March 8, 1993 was the date of a super perigee moon (perigee meaning the closest the moon is to earth during its orbit).

The black wolf that walks across the road in the scene where Randall accidentally hits it on the road was actually an Alexander Archipelago wolf from Santa Clarita, California's animal sanctuary "Hollywood Animals". It was originally from Alaska's Tongass National Forest.

The black wolf's trainers were Clint Rowe, Gayle Phelps, Vikki McMillan and Chris Edrington. Rescuers from the Alaska Humane Society brought this wolf to Hollywood Animals a few years prior to the beginning of this film's production (circa 1990).

Kate Nelligan and Michelle Pfeiffer both starred in Frankie and Johnny (1991) with Al Pacino.

The legendary Bradbury building stood in for Will's publishing house.

Christopher Plummer and Peter Gerety later appeared in Syriana (2005), Inside Man (2006) and Muhammad Ali's Greatest Fight (2013).

Strick worked for about a year on his contributions to the movie.

Elaine May plays the voice of a telephone operator. She and Mike Nichols had been partners in the 1960's in the long-running stand-up comedy Nichols and May. In the act, the two often played characters talking on the phone.

Kate Nelligan and Michelle Pfeiffer appeared in Up Close & Personal (1996) with Robert Redford.

Noted actor Justin Kirk "portrays" Alden's deceased son, in a series of pictures in a photo album. Kirk would go on to work with Mike Nichols again in the HBO adaptation of Angels in America.

Elaine May: The voice of the Mayflower Hotel wake-up call operator.

The infection of Laura does not come from a bite but from the combination of two things. One is most likely the transmission during romance and the other being, as stated in the film, a wolf-like aspect of a person's character. The reason why Kate is not infected is because the second element is missing. She is more of a sheep and does not have the innate element of aggression.