The Avengers (some of them) take on Doctor Doom and lose. The Avengers (others) take on Attuma and lose. The Avengers (still more) take on Namor the Submariner and lose. Luckily, Doom doesn’t play well with others, and the bad guys start fighting each other. In the end, it’s just Doom facing all of the Avengers, pretty evenly matched.
My favorite part of these comics is the covers. Both done by Jack Kirby in typical Kirby style. Nice!