Two universes, human and dinosaur, are colliding - and if one universe isn't sacrificed, then both will be destroyed! And making matters worse, an incursion point between universes has swapped the dinosaur and human versions of the Fantastic Four! But there is another incursion point elsewhere...in Latveria. And Doctor Doom has plans of his own - after teaming up with the only person in the universe he can trust...himself! The FF and the Avengers are brought to their knees, and only the Brothers Grimm can save the day! Plus: The dinosaur Fantastic Four versus the Avengers!