In 2268, Greelee served as head of the ship's biology department. He provided independent study guidance for biology technician Paul Schafer, and invited him to join the science survey of Tau Omega III. After their shuttlecraft crashed, Greelee agreed with senior geologist Lisa Bennit that they should proceed with the survey, but as ranking officer he asked that their scouting party stay together until they'd assessed the area's level of safety. When Bennit noted how quiet it was, Greelee determined with a tricorder that the local animal life was noisy, just on ultrasonic frequencies, and collected a few small specimens. Greelee led a search party after Carl Perez disappeared, but they couldn't locate the missing botanist in the dense jungle.
When the survey team encountered a group of winged Tau Omega III harpies, Greelee scanned them, comparing them to the Skorr. He hoped to communicate with them using a universal translator, but it couldn't be reached in the wreckage, and the skittish harpies eventually attacked. He reached for his phaser, but Fistus had already grabbed it, examined it, and tossed it aside. The fight was interrupted by a rescue party from the Enterprise, and Greelee's team was beamed back to the ship. (TOS - FASA RPG short story: "Planetfall")