Return to sender.

Child star Justin Cooper, whose claim to fame is playing Jim Carrey’s son in the 1997 film “Liar, Liar” when he was 8 years old, revealed in a recent interview on the “Not So Little Rascals” podcast that he received disturbing fan mail from prisoners when he was just a kid.

“My mom did a really good job of kind of, like, shielding me from stuff, you know,” he told co-hosts Jordan Warkol and Blake Collins (who starred in 1994’s “The Little Rascals”) when asked if there were any “overwhelming” or “scary” moments of childhood fame.

“She would tell me later on about, like, prison mail that I would get that she never showed me,” Cooper told a stunned Warkol and Collins.

“Like, letters from people in jail, like, talking about … you know … dudes in jail talking about how they’re such big fans of me and, like, I’m such a cute kid.”

The co-hosts called the bizarre postage “next level” and “wild.”

Cooper, 37, went on to praise his mother for never leaving him alone with anyone on film or TV sets in an industry where some parents tell their kids to “do whatever they tell you to do.”

The actor, who also starred as the titular character in 1998’s direct-to-video “Dennis the Menace Strikes Again,” also opened up about how childhood fame affected his life after the release of “Liar, Liar.”

“I couldn’t really go anywhere in public. I enjoyed it. I thought it was cool,” Cooper said.

He admitted it “probably annoyed” his family “a little bit more,” recalling how people would line up at their hometown buffet to ask for his autograph.

Outside of “Liar, Liar,” Cooper’s lengthier TV credits include roles on “The Boys Are Back” and “Brother’s Keeper” in the ’90s, though he also made one-off appearances in “Full House,” “ER,” “General Hospital” and “Boy Meets World” throughout the decade.

His most recent credit is a 2003 episode of “The Practice.”

These days, Cooper is an executive producer on “The Ben Maller Show” on FOX Sports Radio.

In addition to Cooper and Carrey, “Liar, Liar” starred Maura Tierney, Cary Elwes and Jennifer Tilly, among others.

Cooper was nominated for best performance in a feature film for an actor aged 10 or under at the Young Artist Awards for his work in the Tom Shadyac-directed movie.