"Larry Crowne" serves as a reminder that you can have two of the most likable, bankable stars on the planet together, but strong writing is crucial to making them shine.

Even the combined, blinding brilliance of Tom Hanks and Julia Roberts can't salvage the corny, contrived script — which Hanks, who also directed the film, co-wrote. His longtime friend Nia Vardalos ("My Big Fat Greek Wedding") was his collaborator, and the shticky nature of her style is just overpowering.

Main characters behave in unbelievable ways and say just the right poignant things at just the right times; meanwhile, supporting players are relegated to one-note roles that are straight out of a sitcom, like Cedric the Entertainer and Taraji P. Henson as Hanks' wisecracking, yard sale-loving neighbors.

But the main problem is that Hanks, as the central figure, is as bland as the film's title. Larry Crowne undergoes a major life change when he finds himself downsized out of his job at a behemoth superstore; middle-aged and divorced, he decides it's finally time to go to college. But there's not much momentum, and it's hard to get a handle on who he is beyond his generically pleasant, slightly nerdy demeanor, so his transformation lacks the punch it should have had by comparison.

Larry enrolls in a speech class where Roberts is the frustrated, frequently hung-over professor, Mercedes Tainot. She's having troubles of her own which drive her to make margaritas the second she gets home each day: Her husband, a former novelist, now sits around blogging and watching internet porn. Bryan Cranston, who we know is capable of emotional complexity from his role on "Breaking Bad," merely comes off as a selfish, overgrown adolescent who likes big boobs.

Larry finds his life upended by a fellow student in his economics class: the gorgeous and free-spirited Talia (Gugu Mbatha-Raw). Out of nowhere, she invites him to join her scooter gang, rearranges his furniture and gives him a makeover. It's hard to believe she'd even give him the time of day, much less christen him with a hip nickname ("Lance Corona") and start texting him within minutes of meeting him. Then again, she isn't fleshed out terribly well, either, which makes her motivation even more unclear.

Suddenly, Mercedes is interested in Larry, too — in a romantic way — although she remains so frequently surly, that's hard to figure out, too. In another actress' hands, the performance might have seemed off-putting, even a little sad. But this is Julia Roberts, so simply busting out that famous smile from time to time softens things.

Indeed, "Larry Crowne" seems all too eager to please, even though it features some serious — and seriously relevant — subject matter. The reality of people finding themselves out of work and lost as to how to reinvent themselves after decades in the same job is happening everywhere, every day. Hanks and Co. play the uncertainty of this phenomenon for fluffy, feel-good laughs.

To see Hanks and Roberts playing off each other at their charismatic, witty best, go back and watch them in the biting political satire "Charlie Wilson's War." Larry Crowne could have used a little Aaron Sorkin.

"Larry Crowne," a Universal Pictures release, is rated PG-13 for brief strong language and some sexual content. Running time: 98 minutes. One and a half stars out of four.