Some episodes contain dark and dramatic events, a big example being Munitions where a fire spreads across a harbor and many explosions are seen.

Some episodes contain crashes, explosions, and dramatic incidents that may involve boats running aground.

Characters occasionally insult each other, particularly the Star Tugs and Z-Stacks.

A Tramp Steamer known as Johnny Cuba is described as a smuggler.

Some elements of this series can be seen as dark and edgy for a children's show, such as explosions and crashes. The music, although composed by Mike O'Donnell and Junior Campbell from Thomas the Tank Engine, is also very thrilling.