Revealing mistake: Sebastian Caine wears a latex mask and latex gloves in order to appear near-human. The mask he wears is fairly long, and covers his neck, and the tops of his shoulders and collarbone. However, there is a scene in which Linda and Matt are helping a nauseous Sebastian reach the toilet, where he vomits (invisible fluid) into it. In this scene, when Sebastian breaks free from them and runs to the toilet, we can see that his arms and chest are also visible, skin-colored. The mask he wears only reaches the very base of his neck, so it is possible that the actor playing the invisible man did not realize that the tops of his arms and chest were visible.