Why Did Kevin Spacey Freak Out During A Show?

If you're in London and feel like checking out Clarence Darrow at the Old Vic Theater, please turn off your cell phone. There are the obvious reasons, of course— courtesy to your fellow theater patrons, not wanting to ruin the mood of the play— and then there are the not-so-obvious ones, like the fact that your phone going off could cause Kevin Spacey to break character and yell at you in front of an entire room full of people.

On Wednesday night, when an audience member's cell phone rang in the middle of Spacey's one-man performance, Spacey snapped out of character and reportedly told the audience member, "If you don't answer that, I will." If you've ever seen House of Cards, you know how scary Kevin Spacey can be when he wants to.

And he's not the only celebrity who's been known to put an audience member in their place when they're being rude. For instance, James McAvoy broke character as Macbeth to scold an audience member for filming during not one, but two separate performances. Hugh Jackman and Daniel Craig also got fed up with ringing cell phones while they were performing on Broadway in A Steady Rain. And more recently, Neil Patrick Harris responded in-character as the titular character of Hedwig and the Angry Inch when an audience member tried to cat-call him during a show.

If you want to avoid being yelled at by a celebrity— and then being mocked by TMZ— here are 5 absolute don'ts for a night out at the theater.

Don't Eat

This isn't a movie theater; the actors can hear you crinkling your candy wrappers and loudly chewing! Plus, if you accidentally eat something bad, you could end up like the man who vomited from a balcony in the middle of Paul Rudd and Michael Shannon's play Grace .

Don't Talk

None of the dialogue in the theater should be coming from you unless you're on stage!

Don't Take Pictures

Nope, not even selfies. Patti LuPone called an audience member out on this during a performance in Las Vegas. If plays were supposed to be recorded on camera, we'd call them movies!

Don't Sing Along

If it's a musical, they hired these particular singers and actors for a reason! Leave the singing to the professionals, and then belt out your favorite numbers later from the comfort of your own shower.

Don't Drum

You wouldn't think this would be a problem, but Dame Helen Mirren once left a theater at intermission (in full costume as the Queen of England, I might add) to tell a group of drummers outside to knock it off!