A homebody's best friend disappears

Anna Kendrick and Blake Lively play a snappy duet in A Simple Favor, a thriller with as much comedy as mystery.

In A Simple Favor, Anna Kendrick plays a woman who's determined to be an ideal mother. Kendrick’s Stephanie Smothers is a widow who immerses herself in her son's pre-school activities and in a cooking vlog that she begins with a trademark greeting that defines her vision of an audience. "Hi, Moms,' she chirps.

Stephanie is the kind of mother who brings out the resentments of parents who aren’t quite so gung-ho about pre-school. She drives less conscientious crazy.

Stephanie gives Kendrick an opportunity to go for laughs while keeping us guessing about whether there might be something less controlled under Stephanie's ultra-organized surface.

At first, I thought Kendrick might be overdoing Stephanie's diffidence, offering a near parodic version of a kid-and-kitchen obsessed suburban mom, but her performance grew on me.

Kendrick finds an able comic accomplice in Blake Lively, who plays Emily a woman whose confidence contrasts mightily with Stephanie's timidity. Director Paul Feig (Bridesmaids) makes it clear from the outset that Emily qualifies as a career-obsessed woman who brings a take-no-prisoners attitude to everything she does. When it comes to being a mom, Emily is ... well ... indifferent to the point of neglect.

The movie opens with Stephanie telling her video blog followers that best-friend Emily has disappeared. Emily left her young son with Stephanie, who picked the kid up from pre-school along with her own son. Emily's husband is tending to his sick mother in London.

Once Emily goes missing, A Simple Favor turns into a jaunty, comic mystery built around events that unfold after Emily vanishes.

Enter Sean (Henry Golding), Emily's husband, a novelist who hasn't published anything for a decade but who lives with Emily in a sleekly modern home that evidently is supported by Emily's work as a high-power PR woman for a fashion firm and by ample amounts of debt. Fresh from Crazy Rich Asians, Golding once again is called upon to be handsome, emotionally vulnerable, charming and, in this case, perhaps a bit devious.

I wish the movie had made more time for Rupert Friend, who plays Dennis Nylon (great name), the taste-arbiter who runs the fashion firm at which Emily ruthlessly plies her PR trade.

In this case, though, it's the women -- Kendrick and Lively -- who give the movie its spark as Stephanie turns into an amateur sleuth. She searches for Emily, gradually learning that her friend might not be all that she seemed. Then again, Stephanie isn't all that she seems, either.

As a mystery, A Simple Favor doesn't always work. Feig offers a big reveal too early and an over-stuffed wrap-up threatens to tie the movie in knots.

But Feig keeps A Simple Favor marching to a snappy cadence. He also includes enough satirical garnish to heighten interest without cutting deep enough to draw blood. That's not a criticism. Feig points the movie in the right direction. Simple Favor never extinguishes its sparkle. It's a good-natured helping of venom.