The Summer before their Junior Year in college, Phineas and Isabella have broken up. It has been about a year after their break-up and Isabella wants nothing more than to rekindle the friendship they had 11 years ago, knowing that she had messed up the question of rekindling another relationship.

When Phineas gets brokenhearted, his friends force him to attend the Summer Masquerade Ball. There, he meets the most wonderful girl. There's just one problem: he never asked her name or how to contact her. He sets out to find this mysterious girl, and won't stop 'till he finds her.