Challengers of the Unknown #6

In "Captives of the Space Circus," the Challengers of the Unknown answer a distress call only to be ensnared by a rogue space circus, forced into gladiatorial combat against the monstrous Quadro, the Four-Finned Demons. Trapped among other alien captives, they must survive the arena’s deadly acts—until Prof discovers the strange atmosphere grants them super-strength, turning the tide against their captors.

In "The Sorceress of Forbidden Valley," June Robbins stumbles upon an Aladdin’s lamp during a crash landing on a remote island, only to be overcome by strange fumes. When the Challengers track her down, they uncover a hidden valley where June, now under a mysterious spell, wields unexpected powers—controlled by the sinister Charles Agar, a fugitive from the states.