Unlike cold-blooded neck biters, these poster guys for animal magnetism are hot. So hot that their temperature runs a steady 108 degrees, as anyone who has read Stephenie Meyer's series of gothic romances knows.

That gives them a great excuse to doff their shirts on-screen and expose the physiques they've been pumping up for playing werewolves in The Twilight Saga:New Moon, the sequel to last year's supernatural sensation, due Nov. 20.

Four actors — Chaske Spencer, Alex Meraz, Kiowa Gordon and Bronson Pelletier, all with Native American heritage — join Taylor Lautner, 17, who returns as a hairier, scarier Jacob Black. The plotline finds Jacob growing closer to a distraught Bella (Kristen Stewart) after her vampire beau, Edward, runs off.

Among wolf pack job requirements: the ability to work half-naked no matter what the weather in the Vancouver, B.C., area, where the film has been shooting for several weeks.

"It's not pleasant for the actors," says director Chris Weitz. "But they have all been good-natured. They show up on location in drenching, cold rain, and I say, 'OK, off with the robes.' "