First in... Line?

"It's opening night, and our lead star dropped out! Can you memorize these lines REALLY quickly?"

This play is running super behind schedule, and to make it even worse, the lead had to bail! You're the back-up actor, so you've gotta step in and perform in his place. Problem is, You Forgot Something... YOUR LINES!! No time to rehearse, just memorize them as well as you can and get out there! The show must go on!