On behalf of the Galactic Protectorate, Dodgers and Cadet must venture on a pirate spaceship as lazy sailors to retrieve an invisibility device from the leader of the pirates, Long John Silver the 23rd, who is using it for his purposes. However, things become complicated when X-2 arrives in disguise as well, intending to retrieve the device on behalf of Mars, which then forces all three to work together to avoid being caught by Silver.