It's time for the season finale of "The Big Brain Theory," which finds astronaut and guest judge Buzz Aldrin joining host Kal Penn to see if the final two contestants are up for the toughest challenge yet: creating a portable bridge that can be deployed from the bed of a truck. You mean that doesn't come included? 

While one team goes with complexity and creativity, the other goes with simplicity. Which method will win its team leader the $50,000 grand prize and the one-year contract at WET? Astronaut Buzz Aldrin joins the final episode as a guest judge.

Watch this exclusive clip from the season finale.