Dead Tom was one of the pirates in Muppet Treasure Island. He is called Dead Tom mainly because he is, well, deceased. In fact, he's been dead for so long that all that's left is a skeleton in a hat. He can only participate in roll call when another pirate (Mudwell the Mudbunny) raises his hand and says "Aye" for him. His presence creeps out Captain Abraham Smollett.
When the pirates try to mutiny against Long John Silver, Dead Tom "dies." Mudwell cries over his corpse, kisses his forehead, and blames Long John for shooting him. But Walleye Pike points out that Dead Tom's always been dead, to which Mudwell replies "Oh" and drops the skeleton.