A landmark of early space opera, The Planeteers collects five linked novelets chronicling the scientific odyssey of Blake and Penton as they explore the Solar System. Originally published between 1936 and 1938—with one final installment first appearing in 1966—this saga begins with their flight from Earth's anti-research laws and follows their encounters with shape-shifting Martian lifeforms, dual-brained overlords on Ganymede, and genetically engineered civilizations on distant moons. These hard science fiction tales blend exploration, alien shape-shifting paranoia, and biological speculation in a brisk and inventive chronicle of survival beyond the stars.