Fantastic Four #13 (1963)

In Fantastic Four #13, Reed has discovered a new source of rocket fuel, a meteorite! Of course, he and the rest of the Fantastic Four want to test it out and decide to take a trip to the moon. Sounds like a great vacation, right? Well, things get a little more complicated when they encounter a Russian scientist named Ivan Kragoff who has brought three monkeys with him. Ivan plans on traveling through a cosmic storm that gave the Fantastic Four their powers, and without shielding, these monkeys will absorb more cosmic radiation and get more powers. On the moon, the Fantastic Four find a mysterious Blue Area with air and stumble upon a fight with Ivan and his now super-powered apes. Ivan has become the intangible Red Ghost, his gorilla now has super strength, his baboon can turn into anything, and his orangutan controls metal. The Red Ghost and his super apes capture Sue and the Torch and Thing go on a rescue mission but almost get disintegrated by the Red Ghost's ray. Reed manages to paralyze Red Ghost with a ray he found and saves the day. It's action-packed and full of surprises. Fantastic Four #13 is a classic and a must-read for any comic book fan.