What would you get if you combined the pulpy thrills of a murder mystery like The Girl on the Train with the comedic strokes of Mean Girls and a dash of Gossip Girl for good measure? You’d probably end up with something like A Simple Favor, the new comedy-thriller by Bridesmaids director Paul Feig that probably shouldn’t work on paper, but somehow finds its own niche and vibrancy on-screen.

With its over-the-top characters and preposterous scenarios, this film may not work for those who like their stories to be even remotely grounded in reality. But those looking for a frills-free escape should find exactly that.

Based on the Darcey Bell novel of the same name, A Simple Favor stars Anna Kendrick as Stephanie Smothers, a quirky and self-conscious single mom who runs a successful homemaking vlog from the comfort of her own kitchen.

After the disappearance of her domineering and elusive friend Emily (Blake Lively), Stephanie teams up with Emily’s novelist husband Sean (Henry Golding) to launch their own private investigation and chase the bread crumbs that fall on the trail. As the two begin to dig deeper into Emily’s shadowy past, they realize how little they both actually know her and eventually uncover secrets that have unexpected consequences on their lives.

While everyone in the cast seems to be a good fit for their roles, Lively seems particularly well suited to play the deliciously cartoonish villain who literally struts around with a skull-topped cane. Kendrick brings plenty of charm to Stephanie, though her faux-awkward schtick did wear out its welcome early on and the character is so wildly inconsistent that it becomes difficult to keep up with her at points. Golding, on the other hand, is saddled with a generally lifeless character who is largely reactive to the incidents that occur and he lacks the edge necessary to keep up with the more involving performances that are on display.

Scored with a buoyant French pop-inspired soundtrack and outfitted with decadent, distinctive costume design, the film routinely brings a light, campy touch to some of the darker subject material. This juxtaposition often creates a sort of tonal whirlwind that works more often than it doesn’t and also serves to keep the audience on their toes, so as to better throw them off balance for the story’s inevitable twists and turns. Jessica Sharzer’s densely plotted and often self-aware script is filled with the kind of biting dialogue that constantly shifts the advantage one character may have over another, much like a verbal tennis match at lightning-fast speed.

The screenplay, however, also includes contrivances that are beyond ludicrous and some (perhaps all, depending on the viewer) of the plot twists are easy to spot from a mile away. At two hours long, it also threatens to overstay its welcome and probably could have lost a plot tangent or two for the sake of brevity.

Still, there’s something admirable about the go-for-broke spirit that’s on display, and there’s little doubt that this is the most ambitious movie that Paul Feig has ever directed. A Simple Favor is a film that defies traditional description, and if you’re looking for a twist on a familiar cocktail, this may just hit the spot.

Coming to theaters this weekend:

Night School, starring Kevin Hart and Tiffany Haddish, follows a group of eccentric adult students who are attempting to earn their GEDs from a hard-nosed teacher with unorthodox methods.

Smallfoot, starring Channing Tatum and James Corden, is a new animated fish-out-of-water story about a group of Yeti who cross paths with a human, with either party previously believing the existence of the other was a myth.

Hell Fest, starring Reign Edwards and Bex Taylor-Klaus, is a slasher film which takes place in a horror-themed amusement park where parkgoers remain oblivious to the murderous spree of a masked killer among the rest of the park’s distractions.

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