Charlie Sheen will make a surprise appearance at the MTV Movie Awards 2012.

The former Two and a Half Men actor has been lined up for a stint on stage at this weekend's ceremony according to a report. Charlie will introduce a tribute to party films and will announce musical act Wiz Khalifa, who was recently arrested for marijuana possession.

"Even though Charlie has cleaned up his act, he still has a sense of humor about his out-of-control days," a source told E! News.

"It's all going to be a really big party moment," another source said.

Also at the event on Sunday night Kristen Stewart will present a section with her Snow White and the Huntsman co-star Chris Hemsworth. Meanwhile, her boyfriend and The Twilight Saga: Breaking Dawn - Part 2 co-star Robert Pattinson will not be attending this year. Russell Brand will host the bash.