The film is directed by Harry Bradbeer from a screenplay by Jack Thorne that adapts the first novel in The Enola Holmes Mysteries series by Nancy Springer.

In the film, Enola travels to London to find her missing mother but ends up on a thrilling adventure, pairing up with a runaway lord as they attempt to solve a mystery that threatens the entire country.

Originally planned for a theatrical release by Warner Bros. Pictures, the distribution rights to the film were picked up by Netflix due to the COVID-19 pandemic.

The flower cards left by her mother reveal secret messages and lead to hidden money, which Enola uses to escape disguised as a boy.

Disguised as a proper Victorian lady, Enola continues to trace Eudoria, leaving cryptic messages in the newspaper personal advertisements.

By February 2019, a film adaptation of the book series The Enola Holmes Mysteries by Nancy Springer was in development at Legendary Pictures, with Millie Bobby Brown producing and starring in the title role and Harry Bradbeer set to direct.

[1] The film adapts the first book, The Case of the Missing Marquess, in which the younger sister of famed detective Sherlock Holmes goes on an adventure after her mother's disappearance.

She later told her father they should make it into a film and partnered with Legendary Pictures, the same company she had previously worked with on Godzilla: King of the Monsters.

[4][5] Bradbeer was enthusiastic about the script since it combined his interest in stories about "dysfunctional families coming to terms with each other" with his love of Sherlock Holmes.

[3] Brown took the opportunity to improvise, something she would not do on television series Stranger Things, which is heavily scripted and because the character of Enola Holmes allowed for it.

[15][16] Benthall Hall had not previously been used as a filming location, and the production design team received great help from the head groundskeeper who allowed the place to become overgrown to achieve the look they needed.

False walls were put up and inspired by the Arts and Crafts movement they included plant motifs in the decorations and period wallpaper.

[23][24] The Conan Doyle Estate filed a lawsuit against Netflix over the film, claiming it violated copyright by depicting Sherlock Holmes as having emotions.

"[27] On October 30, 2020, lawyers for the defendants filed a motion to dismiss, saying the estate was unfairly attempting to prevent the fair use of characters that are "undeniably in the public domain".

[34] Originally intended to be a theatrical release by Warner Bros. Pictures, in April 2020, Netflix picked up the worldwide distribution rights to the film due to the COVID-19 pandemic, except for in China.

[46] In January 2021, Enola Holmes ranked 7th on Business Insider's Biggest Netflix Original Movies of All Time with 78 million viewership.

The website's critics consensus reads: "Enola Holmes brings a breath of fresh air to Baker Street – and leaves plenty of room for Millie Bobby Brown to put her effervescent stamp on a franchise in waiting.

[49] Peter Debruge of Variety called the film an "entertaining franchise starter" and praised Brown's performance, stating that "[her] acting style recalls the effusive spontaneity Keira Knightley brought to Pride and Prejudice, shattering the straitlaced propriety of so many Jane Austen adaptations before it."

Debruge found the film "more tasteful in its high-energy storytelling than Guy Ritchie's recent Sherlock Holmes movies, and considerably more fun than [2019]'s Nancy Drew reboot.

"[51] Ann Hornaday of The Washington Post wrote: "Enola Holmes offers brisk and exuberant escape from the heaviness of modern times, with its leading actress lending her own appealing touches to the journey.

"[52] Ella Kemp of Empire magazine wrote: "Well-intentioned if sometimes lacking in subtlety, Enola Holmes offers a fine, spirited reminder that a traditional story can always be retold – although it might need more refined teachings on feminism next time.

"[54] In a negative review, Mick LaSalle of the San Francisco Chronicle wrote: "A bright young actress, a movie-star actor and a potentially interesting concept gets smothered in 128 minutes of colorful, empty nonsense.

[63] On May 13, 2021, Enola Holmes 2 was officially announced, with writer Jack Thorne and director Harry Bradbeer returning while Brown and Cavill would reprise their roles.