Lady Gaga takes a chilly dip for charity

Barry Brecheisen/Invision/AP

Lady Gaga and Vince Vaughn plunged into the icy waters of Chicago’s Lake Michigan on Sunday at a fundraiser for Special Olympics.

Special Olympics Chicago President Casey Hogan said Gaga and Vaughn did the plunge with more than 4,500 other participants. Hogan says the singer’s appearance was “a very nice surprise.”

Newly engaged Gaga’s fiancé Chicago Fire actor Taylor Kinney took the frigid dip with her.

Chicago native Vaughn took the plunge in a Chicago Blackhawks jersey and jeans. The actor went in up to his knees, then eased himself into the water.

Last year, comedian Jimmy Fallon jumped in wearing a suit and tie, and helped raise more than $1 million.