Peter Raeder, once a skilled ace pilot in the Commonwealth's war against the secessionist Mollies, lost his hand and his flight privileges in a fierce battle. He then joined the crew of the Invincible, a swift and formidable carrier, as a Flight Engineer, ready to confront the Mollies and their alien allies. During his first mission, he encountered pirate raiders, Mollie attacks, and a secret saboteur who nearly destroyed the Invincible before Raeder exposed him.