Having saved humankind with the aid of a benevolent alien species called the Vulcans, Captain Brock, a part human, part machine, cyborg, can't wait to resume his favorite activity — space exploration. However, he discovers his departure will, again, have to be put on a back burner. He is told there is one more dire situation for him to resolve.

As is revealed, Captain Brock, while accompanied with his buddy and good friend, Chairman Yang, along with Number One, a highly intelligent, android, is dispatched to stop a deranged alien Captain who is in control of a massive, planet busting, space ship, and who has gone rogue and is threatening the entire galaxy.

During his critical mission, Brock encounters and becomes friends with a member of another intelligent species, called the Dneirf, who is interested in becoming a cyborg similar to Brock. While attempting to grant the wish of the new encounter, Brock discovers the desire to become a cyborg doesn't end with his new alien friend.

The questions are, how can Brock stop the insane Captain, who, with his powerful ship, can destroy the good Captain Brock as easily as stepping on a bug, while at the same time, honor the many wishes to become cyborgs?