"A Simple Favor" is not based on a true story; it is adapted from the 2017 novel of the same name by Darcey Bell. The film, directed by Paul Feig and released in 2018, combines elements of mystery, thriller, and dark comedy. It follows the story of a woman who tries to uncover the truth behind her friend's sudden disappearance. While the plot features relatable themes of friendship and betrayal, its characters and events are fictional.

In "A Simple Favor," Emily Nelson, played by Blake Lively, goes missing after asking her friend Stephanie (Anna Kendrick) for a favor. It is later revealed that Emily faked her own disappearance. She had been involved in a series of deceitful actions, including faking her own death to escape her troubled life and marriage. The plot unfolds as Stephanie uncovers the truth about Emily's manipulations and dark secrets, leading to a dramatic confrontation between the two characters.

"A Simple Favor," directed by Paul Feig, is a blend of mystery, dark comedy, and thriller, featuring Anna Kendrick and Blake Lively. The film follows a vlogger who investigates the disappearance of her glamorous friend, leading to unexpected twists. It has received positive reviews for its engaging plot, sharp humor, and strong performances, particularly from Lively. If you enjoy stylish thrillers with intriguing plots and a dash of wit, it’s worth watching. However, viewers seeking straightforward narratives might find it less appealing.

No, Blake Lively does not play both twins in "A Simple Favor." She portrays the character Emily Nelson, while the character's twin sister, who appears in the film, is played by another actress. The film, directed by Paul Feig, features a mystery involving the disappearance of Emily and her complex relationships, but the twin aspect does not involve Lively playing both roles.