'I Want You Back' review: Great performances elevate this predictable rom-com

WHAT IT'S ABOUT Jenny Slate and Charlie Day star in "I Want You Back," a new romantic comedy that proudly indulges in the familiar genre tropes.

The stars play Emma and Peter, who meet after being dumped by their respective significant others. Ignoring the fact that they are perfect for each other, they hatch a plan to win their exes back.

This involves each person breaking up the new relationship of the other's former flame.

So, Emma must seduce Logan (Manny Jacinto), the middle school drama teacher now dating Peter's ex-girlfriend Anne (Gina Rodriguez). At the same time, Peter is tasked with befriending Emma's ex-boyfriend Noah (Scott Eastwood), a personal trainer, and driving him apart from new girlfriend Ginny (Clark Backo).

MY SAY There's not a romantic comedy cliché left off the screen in "I Want You Back," starting with the reality that it's a nearly two-hour movie that would end in 10 minutes if Emma and Peter simply recognized what was right in front of them.

But these characters don't know they're in a movie and that they have decades of predecessors to look toward as examples. So the success of the picture depends on the extent to which the actors can compel the audience to forgive the postponing of the inevitable.

By that standard, "I Want You Back" delivers exactly as it should. It's easy to overlook just how predictable and obvious all of it is, because the stars are so perfectly cast.

Slate and Day showcase their neurotic, self-effacing charm. They understand exactly what the movie requires and know how to elevate the material.

A key example: When Emma and Peter meet cute in the wake of the breakups, both are crying on the stairs in the office building their employers share — she's a receptionist for an orthodontist and he works for a nursing home business.

It's a moment that's ridiculous if it's thought about logically, but affecting as it plays out because the actors invest it with the exact right combination of humor and seriousness.

Their performances allow for the ill-advised and obviously doomed plot to get the exes to reconsider to become less about any particular development in that journey. Instead, it's reframed as the larger picture of two people learning to embrace that they might simply be at a different point in their lives than those they once thought were their soul mates.

Nothing in the movie exemplifies this better than a scene where Emma becomes conscripted at the last second to fill in as Audrey for a tech rehearsal of a middle school production of "Little Shop of Horrors."

It makes no sense and does nothing to advance the plot, but as Slate belts out "Suddenly Seymour," she invests the moment with emotion that seems to have been derived from somewhere deep within.

It's funny and sad and relatable, too. That's acting for you.

BOTTOM LINE Even if it's clichéd and predictable, this is a perfect movie for romantic comedy fans.