They were freezing for a reason and so was GreaterBayShore’s Matty Denz Saturday at Islip Town Beach, where dozens took to the near-freezing cold waters of the Great South Bay.

The polar plunge benefitted Gavin’s Got Heart, which provides financial and emotional support for families with children affected by congenital heart defects.

This was the third annual charity plunge. In the video above, see our host Matty Denz plunge into the icy bay (twice). Scroll down for 20 photos.

Photos & Video by Andrew Theodorakis/Yellow House Images for GreaterBayShore