The Avengers #105

 "In the Beginning Was... The World Within!"

Quicksilver is MIA and his inconsolable sister, the Scarlet Witch, has locked herself in the Avengers’ monitoring room until she finds her lost brother.

The Black Panther returns to the mansion after an adventure with Daredevil just as the Scarlet Witch bursts into the room with information about a report of scientists in Chile that has been kidnapped by strange attackers. Iron Man, Hawkeye, Scarlet Witch, Black Panther, the Vision, and Thor (who is accompanied by Sif, a visitor to Earth with a number of other Asgardians) travel to Chile to check out the strange occurrences.

In Chile, they find a secret series of cavernous tunnels that lead to the Savage Land. There, they are attacked by the Savage Land Mutates but easily fight them off. Traveling to the village Magneto built in the Savage Land, they find it in ruins and also find the costume previously worn by the X-Man known as the Angel.

Once again, the Mutates, led by Vertigo, attack. The Avengers gain the upper hand until Vertigo unleashes the Mutate known as Lorelei who uses her mutant singing power to lull the Avengers into a trance-like state. This, however, does not affect the Vision, who easily defeats both Vertigo and Lorelei.

After the battle, the Scarlet Witch approaches the Vision about his cold behavior which the Vision passes off because he is "just an android."

After saving the scientists and returning home, the Avengers continue their search for Quicksilver. The Vision stays behind to brood, contemplating taking up the Grim Reaper's offer to become human.