The film title in Korean (Ah-ga-ssi) means ''The Lady'' referring to Lady Hideko, while the English/International title is The Handmaiden referring to Sook-hee.

Both Japanese and Korean were spoken in the film by the predominately Korean cast. Before shooting, the Korean actors were all assigned Japanese teachers to study the script and learn to speak Japanese. After the screening at Cannes, actress Min-hee Kim was applauded by Japanese journalists for her proficiency in Japanese.

Based on the novel "Fingersmith" by Sarah Waters (published in 2002 by Virago Press). The novel is set in London during the 19th century, but the film is set in Korea in the 1930s, under Japanese colonial rule.

The pornographic painting with Octopus in Part 1 of the film was 'The Dream of the Fisherman's Wife', work of Katsushika Hokusai (1760 - 1849), Japanese artist of the Edo period. The pornographic story read by Hideko's aunt in Part 2 was an excerpt from Jin Ping Mei (The Plum in the Golden Vase), a Chinese erotic classic.

Tae-ri Kim was a fan of Min-hee Kim's work before they met. She did not know that Min-hee would be playing Hideko during the audition. It was only in a meeting with Park after being chosen, that Park asked who her favorite actor was. Tae-ri answered Min-hee and Park was very delighted. Tae-ri and Min-hee gradually built up their friendship and trust since 2014 during the preparation stage. During Tae-ri's Best New Actress acceptance speech at Buil Film Festival 2016, she dedicated the award to Min-hee whom she ''fell in love with at first sight''.

Before filming, director Park sent the completed script to source writer Sarah Waters for comments. Waters liked the script but felt that it is more appropriate to say that the film was ''inspired by" the novel Fingersmith.

According to the actor Jung-woo Ha, as Count Fujiwara is a Con Man, he has proficiency in lies and deceit. However, one way to see his intentions is by the language he's speaking. He speaks Japanese when he's lying but speaks his native Korean when telling the truth.

Actress Tae-ri Kim was selected for her role through auditions which had approximately 1,500 applicants.

Director Park described the character Lady Hideko as a white cat, elegance and distanced.

For the theatrical release of the film, the subtitles were color coded to differentiate the Asian languages spoken throughout the film. White subtitles were used for Korean while yellow subtitles were used for Japanese.

During the script writing stage, Director Park and his female co-writer Seo-kyeong Jeong often sought the advice of one of Chung's best friends, who was a queer woman, for advice on the sensibilities of queer women.

Lady Hideko is named after Japanese actress Hideko Takamine and Sook-Hee is named after Sue (Susan Trinder) in the original novel 'Fingersmith' by Sarah Waters.

Director Chan-wook Park decided to cast Tae-ri Kim as Sook-hee at the audition in 10-15 minutes.

During shooting, Tae-ri Kim ran around exploring things, while Min-hee Kim was quietly in her own world. Park and Jung-woo Ha (who played the Count) thought Tae-ri was like a puppy and Min-hee was like a cat, somewhat resembling their characters in the film.

Feature film debut of Tae-ri Kim.

Pre-sold to 116 territories ahead of its theatrical release.

Filming began June 15, 2015 in Kuwana, Mie Prefecture, Japan. Filming was completed on October 31, 2015. Shooting took place in various locations in Japan and South Korea.

The film became the highest-grossing Chan-wook Park-directed film in the United States. It also became the highest-grossing foreign language film in the United Kingdom in the 2017. Amazon handled the releases in both countries.

The song played in the official trailer of this film is "Red Sex" by Vessel from their album "Punish, Honey" released in 2014.

Several of the characters in this film, adapted from the novel Fingersmith by Sarah Waters, were significantly altered for this version's script. Gentleman (Count Fujiwara in the film) was a gay man in the novel whose interest in Maude (Lady Hideko) was purely monetary. In the film, the Count is a suave womanizer. Uncle Kouzuki's novel counterpart is tamer, although he isn't a saint, he was never evil and prone to cold blooded torture like his film counterpart.

Included among the "1001 Movies You Must See Before You Die", edited by Steven Schneider.

During filming, due to the summer heat, Tae-ri Kim always brought a big bottle of beverage - either coffee, tea, or mineral water. She shared her drink with fellow actress Min-hee Kim using the same straw she's using. Min-hee Kim said during Arirang TV Showbiz Korea interview that Tae-ri Kim just placed the straw into her mouth.

In the bathtub scene where Lady Hideko complains of her sharp tooth cutting her mouth, Sook-hee files it down with a thimble, which is an ancient protective cap worn over the fingertips. It was mostly used for sewing to defend against the needles.

For the lesbian lovemaking scenes between the two female leads: All the crew members were asked to leave the set and only a female staff holding the boom microphone was present. The scenes were filmed with a remote controlled camera. On the date of shooting, all visitors were not allowed to be near the shooting area. All male crew members had a day off on the shooting day. The bathroom set in Hideko's room was made into a resting area for the two actresses to relax between takes. The bed scenes were shot during the early stages of the production as Park thought it was stressful and burdensome for everyone. During pre-production, everything has been choreographed and discussed between Park and the two actresses who were fully-dressed. Tae-ri Kim said she felt slightly insecure with performing the simulated lesbian sex scenes, but Min-hee Kim reassured and energized her.

Before finishing the novel Fingersmith, Director Chan-wook Park has decided to make a film with a happy ending.

In Part 3, Sook-hee's passport shows that her familial status as "single woman", her profession is "student", and her height as 1.67 meters (5'5"). In the last part of Part 3, the Count's fake passport shows his name as Go-Pandol, his familial status is "head of the family", works as an artist, and he is 1.81 meters (5'9") tall. Both passports show their domicile as Kyungsung-bu (the name of Seoul during Japanese occupation).

In the infamous basement scene containing the jars of severed body parts, a live octopus can be seen in a tank among the jars, presumably as a torture method. This is an intentional homage by Chan-wook Park to his film Oldboy (2003) where Min-sik Choi had to eat a live octopus in the sushi restaurant scene.