Lady Gaga takes the plunge with fiancé Taylor Kinney in icy charity challenge

Lady Gaga and her fiancé Taylor Kinney took the plunge in icy water on Sunday.

Gaga, 28, braved the cold water of Chicago's Lake Michigan for the annual Polar Plunge event to raise money for the Special Olympics.

Chicago Fire actor Kinney hoisted the Poker Face singer onto his back as he waded into the icy water before dunking them both under.

Gaga, who had shunned her usual eccentric attire for a black t-shirt and black skinny jeans, emerged with ice in her hair after completing the dip, but described the whole experience as "awesome".

Also taking part was Kinney's Chicago Fire co-stars David Eigenberg, Randy Flagler, Jon Seda and Brian Geraghty as well as Wedding Crashers star Vince Vaughn.

Wearing a Blackhawks shirt Vaughn said, "It's too late to turn back now," as he dunked himself into the freezing temperatures.

The 44-year-old actor was chosen as the guest of honour after a successful social media campaign with the #VinnyDippin was started on Twitter.