"The Galileo Seven" is the sixteenth episode of the first season of the original science fiction television series, Star Trek, broadcast by NBC on January 5, 1967. It was written by Oliver Crawford, inspired by the film Five Came Back, and it was directed by Robert Gist.

In this episode, which featured the debut of the shuttlecraft, First Officer Spock leads a scientific team from the Enterprise aboard the shuttlecraft Galileo on an ill-fated mission.

On stardate 2821.5, the Federation starship USS Enterprise, under the command of Captain James T. Kirk, is en route to Makus III, delivering much-needed medical supplies to be distributed at the plague-ridden New Paris Colony. The ship passes close to a quasar-like formation of four star systems identified as Murasaki 312, which Kirk's standing orders require him to study. Since the Enterprise is not scheduled to rendezvous for five days, Kirk decides to send a science team composed of Science Officer Spock, Chief Medical Officer Dr. McCoy, Chief Engineer Scott, and four other specialists from the crew out in the shuttlecraft, Galileo, to investigate the formation.

Soon after launch, the shuttle is pulled off course and out of the Enterprise's sensor range. Spock makes an emergency landing on the planet Taurus II, a rocky, fog-shrouded world in the middle of the Murasaki phenomenon. Crewmembers Latimer and Gaetano scout the area, eventually encountering Taurus II's native inhabitants: giant ape-like creatures armed with enormous spears and shields.

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