Credit: Fotos International/Getty Images

Rumors have been circulating the Internet about Castle co-stars Nathan Fillion and Stana Katic, and the status of their off-screen relationship. While some people claim the two aren't very friendly, others contend the pair are thick as thieves.

Today, Stana tweeted a picture of a concert ticket stub from 2008 that proves two things: 1) She has excellent taste in music, and 2) She and Nathan are not, and have never been, mortal enemies.

"OMG! Look what I found!! The concert tix that @NathanFillion and I went to whilst filming the pilot of Castle!!" she tweeted along with a picture of the stub.

Stana seems pretty stoked to have found the ticket, which leads us to believe the pair had a fantastic time. Plus, we can totally picture them busting out a beer-fueled rendition of "Hungry Like the Wolf."

Source: Twitter

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