|Zac Efron||Young Mike O'Donnell|
|Thomas Lennon||Ned Gold|
|Matthew Perry||Adult Mike O'Donnell|
|Tyler Steelman||Ned Gold (Teen)|
|Allison Miller||Scarlet (Teen)|
|Melora Hardin||Principal Jane Masterson|
|Jim Gaffigan||Coach Murphy|
Mike O'Donnell was a high-school basketball star with a bright future, but he threw it all away to marry his girlfriend and raise their child. Almost 20 years later, Mike's marriage has failed, his kids think he's a loser, and his job is going nowhere. He gets a chance to correct the mistakes of his past and change his life when he is miraculously transformed into a teenager, but in trying to fix his past, Mike may be jeopardizing his present and future.