The second chapter in the Ultimate Galactus Trilogy, Ultimate Secret was begun by Warren Ellis and Steve McNiven, but McNiven's schedule caused him to drop out of the series after the second issue. Tom Raney replaced him, but the series still suffered a long delay before all four issues were finally published.
Ultimate Secret was very different in tone from the first series in the trilogy, Ultimate Nightmare. It adopted a more high action, superhero adventure story than Ultimate Nightmare's scifi horror story. It centered around the debut of the Ultimate version of Captain Marvel but also debut the Ultimate versions of Carol Danvers, Yon-Rogg and the Kree race in general.
