Jimmy in "That Thing You Do" is Totally Shredded Now -- Check Out His Shirtless Photos

Johnathon Schaech – the scrawny singer from 'That Thing You Do' – has bulked up ... and no, this isn’t an April Fools joke.

The sexy actor has clearly been hitting the gym hard and he’s got a freakishly fit physique to prove it. Check out the gallery to see Johnathon’s flexin’ photos.