A brave Jimmy Fallon participates in the Chicago Polar Plunge 2014 at North Avenue Beach in Chicago, Illinois.
Fallon waded into the icy water next to NFL player Israel Idonije.
Before taking the plunge, Fallon addressed the crowd, '"If you hear a scream like a little girl's, just know that Jimmy Fallon is swimming in Lake Michigan."
Wearing a suit and tie, Fallon waded in, turned toward the beach and then fell backwards, going completely under water.
The crowd cheers Jimmy on after his dip in 10 degree temperatures.