Colonel Hanrahan

Colonel Hanrahan is the Chief of ship security and Commander of the marine contingent on the Constitution, and later the Warrior, during the events of book 1. He is corrupted by the Swarm in book 2. In book 2, Proctor detects a Swarm meta-space signal during Granger’s meeting with the Dolmasi Admiral, and she is unable to figure out if it's coming from the Dolmasi, Doc Wyatt, or Hanrahan. It turns out its coming from all three, as Hanrahan is corrupted by that point, and later holds engineering hostage during a pivotal battle. Granger ends up shooting Hanrahan in the head, after confusing the colonel with his own vestigial meta-space link he still has from his “vacation”.