Tom Corbett Space Cadet #4

Tom Corbett and his fellow space cadets visit Mars, where they discover ancient ruins and encounter a model of the latest spaceport control tower. After being dismissed from a class, Tom and Roger befriend a Venusian swamp monkey and smuggle it aboard the academy ship. The cadets are forced to rescue Captain Strong and Astro from outlaws on a desert planet, navigating through a pyramid structure while pursued by solar guardsmen. The rescue culminates in a confrontation where the cadets must prevent a duel between the captured officers and their captors.