Once I was playing Gwendolyn in Importance of Being Earnest, and in the scene where I show my diary to Cecily, I burst out laughing at a strategically placed practical joke in the form of an illicit picture (keep in mind my character's supposed to be huffy and pissed), and to make matters worse, I stopped the scene to howl with laughter while my co-star looked on in horror. To make things worse, I turned to the audience, said, "I'm sorry. It's closing night.", and continued to laugh myself stupid for the next 2 minutes. Then during intermission, my director ripped me a new one, and they had to delay the start of Act 2 because I was crying so hard in my dressing room.
"It's not always about you!!!" (But if you think I'm referring to you anyway, then I probably am.)
"Good luck returning my ass!" - Wilhemina Slater
"This is my breakfast, lunch and f***ing dinner right here. I'm not even f***in' joking." - Colin Farrell