Chief Petty Officer Garrison was a Human male enlisted crewmember serving in Starfleet in the 23rd century. Garrison was assigned to the operations division aboard the USS Enterprise in 2254, working as one of the ship's communications officers.
Garrison was at the communications station when the Enterprise intercepted an old-style radio wave distress signal from the SS Columbia. At Captain Christopher Pike's request, Garrison accompanied the initial landing party to Talos IV which discovered the illusory survivor's camp created by the Talosians.
He later accompanied "Number One" to the surface in the failed attempt to use a laser cannon to gain access to the Talosians' underground settlement. He then joined a third landing party that intended to beam directly into the Talosian settlement, although Talosian interference allowed only "Number One" and Yeoman J.M. Colt to transport.