The Enterprise is sent to investigate Klingon activity in the galactic core. They encounter a shuttlecraft piloted by Thomas Clayton, from the long-lost ship, the USS Rickover. Clayton is also an old friend of Kirk's, a former roommate from his time at Starfleet Academy.
Kirk is prepared to dismiss his unfortunate friend as a madman until a mysterious force seizes control of the ship. Clayton declares the Enterprise is now going to meet his new god.