The X-Men were ambushed and are now at the mercy of the deadly Shi'ar renegade Deathbird and her sinister accomplices, the alien Brood (see the last pages of Uncanny X-Men #161 to see how it happened). Now, the feral X-Man Wolverine fights the battle of his life within and without as a Brood embryo attempts to hatch inside his body, thus killing him and usurping his body and mind - forever!