If you're looking to get cast in a big summer blockbuster at some point in the near future, take a tip from Pacific Rim star Charlie Day: just give a "rat speech" level performance.

What is the rat speech, you ask? First of all, your life has been severely lacking so far. Second of all, get ready for your life to officially start right now: The rat speech originated in a season six episode of It's Always Sunny in Philadelphia, and involved Day's character, Charlie Kelly (also known as the King of the Rats), waxing poetic about the lives of rats and whether or not they're really less important than the lives of humans.

It's a brilliant scene for many reasons, but Day's performance as a completely haunted Charlie Kelly was undoubtedly the most genius part. And, because Pacific Rim director Guillermo del Toro has amazing taste in life, he decided to cast Day in his film because of it. If you remember, the director is a huge It's Always Sunny fan, and even appeared on an episode in 2012 playing a man who screams about eating babies. It was a delightful role.

Day explained the story during an appearance on Late Night With Jimmy Fallon yesterday:

"I got a call from Guillermo del Toro, the director...apparently he's a huge Sunny fan. There was an episode where I was bashing rats, called 'Charlie Kelly: King of the Rats,' and I was like haunted from murdering rats, and he said to himself, 'That's my guy.'"

You really have to watch Day explain the story himself, because his impression of del Toro is kind of amazing. Actually, his whole interview is kind of amazing, because he's Charlie Day, and amazing is his middle name (probably). 

So, there you have it: the quickest way to gain a role in one of the biggest summer blockbusters in years is to give a lengthy, brilliant monologue about the purpose of human life compared to that of rats. The more you know!

You can check out Day's interview on Late Night above, and watch his infamous rat speech down below. Yes, the quality of the video sucks, but when the quality of scene is as epic as that one is, it balances out. 

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[via Uproxx]