Clark is stuck in a time loop: he has woken up and relived the same monotonous Monday 309 times. Day 310 turns out to be different: his usual torturous math class is interrupted by a boy he has never seen before in all his previous Mondays. Throwing caution to the wind, Clark joins effusive and effervescent Beau on a series of errands across the Windy City: he never imagines that anything will really change, because nothing has in such a long time. And he doesn't expect to fall this hard or this fast for someone in just one day. How do you build a future with someone if you can never get to tomorrow?