centers on the arrival of a new tug, Sunshine, at Bigg City Port and the rivalry between the Star Tugs and the Z-Stacks. The Z-Stacks, led by Zorran, sabotage the Star Tugs' attempt to dock the grand ocean liner, The Duchess, by making it appear as though Sunshine was responsible for the near-disaster. Framed and feeling ashamed, Sunshine runs away and is later found by the other tugs, who learn the truth from Izzy Gomez. In the end, Sunshine is welcomed into the Star Fleet, and Captain Star teaches the others not to jump to conclusions.
