The FF return home from an extra-dimensional adventure to find the Baxter Building and everyone in it just a little bit off. Their usually-angry neighbors are suddenly all too happy to chat. They come bearing strange gifts, and oddly enough, seem extremely interested in the FF's powers. Soon it becomes obvious that the Baxter Building has been invaded by shape-shifting aliens - THE SKRULLS! But as the FF discover, whenever you deal with Skrulls, there's always more going on than meets the eye!