After returning to Earth from the incident with V'Ger, the Enterprise gets a second attempt at their "routine training mission". Once again, though, events conspire against it being a simple "shakedown" cruise. A Klingon vessel intercepts, attempting to take the newly refitted Enterprise back to the Klingon homeword as a prize. Kirk outwits the Klingons, though, forcing Starfleet to reconsider whether his best use is as Chief of Starfleet Operations. They recommission him as commander of Enterprise and send him out on a second five year mission.