The Rocketeer: Breaks Free (The Rocketeer: Breaks Free #3)

Peevy and Rose narrowly survived the U-boat attack on San Francisco, but as witnesses to the danger, they are now targets! For Cliff to protect his friends, he's going to need to rely on special allies, including a mysterious figure from his past who previously had designs of his own for the rocket pack. Defeating the enemy will require some desperate measures, including the previously unthinkable - breaking into Alcatraz!