An alien is banished from his planet and sentenced to live on Earth in human form. There's one problem with his disguise, though -- every so often, his human head explodes, revealing his identity. This leaves the alien with no choice but to intermittently pop off the heads of arbitrary people and use them until it's time for a replacement. Meanwhile, officers Diana (Rae Dawn Chong) and Charles (Don Gordon) begin to trace the trail of headless bodies back to their extraterrestrial source.