A widowed mommy vlogger with a sunny, go-getter disposition. A sophisticated, sharp-tongued workaholic mother who does not suffer fools gladly. Neither young woman may be quite what she seems, and a sudden disappearance causes a seismic shift in both their destinies. A jaunty mystery and tart black comedy in one, "A Simple Favor" keeps its twists coming, some more plausible than others but all working in the shadow of a wickedly naughty grin. Adapting from Darcey Bell's 2017 novel, director Paul Feig (2016's "Ghostbusters") and screenwriter Jessica Sharzer (2016's "Nerve") take the essence of their source material while making it their own. As for leads Anna Kendrick (2017's "Pitch Perfect 3") and Blake Lively (2016's "The Shallows"), they are terrific, bringing mordant zest and gravitas to their respective roles.
Stephanie Smothers (Anna Kendrick) is the kind of over-achieving mom who has to be talked down from volunteering for every parental duty on son Miles' (Joshua Satine) elementary classroom event sign-up sheet. Emily Nelson (Blake Lively), the chic director of public relations for fashion designer Dennis Nylon (Rupert Friend), is not. They are starkly different parents and people, but become unlikely friends after meeting during their children's afterschool playdate. When Emily must work late one day, she asks a simple favor of Stephanie: pick up son Nicky (Ian Ho) and watch him for the evening. Two days later, Emily still hasn't returned, and no one—not Emily's husband Sean Townsend (Henry Golding), in London caring for his ailing mother, and not Dennis Nylon himself—has any idea where she is. As the police get involved and an investigation into Emily's disappearance begins, Stephanie finds herself drawing closer to Sean while finding a personal flair for amateur sleuthing. In light of media attention over the case, her mommy vlog goes viral.
See Dustin Putman, TheFilmFile.com. for full review