Ryan Reynolds thought he would be taken into custody for a prank he played on the set of Just Friends in 2005.

The actor recently appeared on talk show host Conan O'Brien's podcast, Conan O'Brien Needs a Friend, and spoke about the prank that made him "scared" of going to jail.

The movie was filmed in Regina, Saskatchewan, Canada, and Reynolds jokingly put a message over the welcome sign that town officials did not find funny...at first.

"It’s one of my few times that I've ever been scared of going to jail, because we, just as a joke, me and the art department, we made a sign that would go over, it would snap over the 'Welcome to Regina' sign. And it just said, 'Welcome to Regina, which rhymes with fun.' And I got in trouble, though."

He continued, revealing that officials eventually considered the act humorous, but only because the makeshift sign snapped off.

"They thought it was funny because it snapped off. So at first it was vandalism, and then it was class."

The Proposal standout is no stranger to a harmless set prank and has actually been in a "prank war" with Deadpool & Wolverine co-star and best friend Hugh Jackman since 2015, per Entertainment Weekly.

People recalled an instance when Reynolds had socks made with Jackman's face on them to celebrate the X-Men actor's 53rd birthday.

For more, read Hugh Jackman Reacts To Martha Stewart's Bold Comments On Pal Ryan Reynolds.

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