"If you could turn back time? could you win back the love of your life?" That's the problem puzzling Stillman, a physics genius recently dumped by his stunning girlfriend Debbie. So, after creating a timeline of their romance and a machine to rewind the past, he grabs his wing man Evan and sets off to right every wrong he made with Debbie. But as this insane comedy proves, there are some mistakes too perfect for even science to fix.