Liam Neeson Strips to Pink Briefs for Charity

"Taken 2" star Liam Neeson showed off the goods yesterday on "The Ellen DeGeneres Show" -- stripping down to a very revealing pair of bright pink briefs!

But why?!

The 60-year-old actor took it all off for charity, as Ellen is raising money for breast cancer research this week on her show.

For the stunt, Neeson shed his robe and went nearly naked as he stepped into a modified version of a classic dunk tank.

If the selected audience member -- a cancer survivor herself -- or Ellen could hit the target with a ball, a big bucket of water would drop all over Neeson's head.