Ultimate Galactus Vol. 2: Secret

A new propulsion system devised by the U.S. government puts Mars just days away. It creates interplanetary opportunities unprecedented for the human race. But someone - or something - wants Earth's progression into space to stop. What does that mean to the Ultimates and the Ultimate Fantastic Four! And yes, that mysterious white-and-green figure is Ultimate Captain Marvel! Collects Ultimate Secret #1-4.