Ferret

Serin Osman: "Investigators with teeth. You slip into a hole, find the rats, and—"

Mark-G313: "And kill them?"

Serin Osman: "Sometimes. But I was going to say, "fix the problem." Sometimes, that might mean rescuing people instead of killing them."

— Rear Admiral Serin Osman explains the purpose of Ferret teams

Ferrets are covert special operations units under the authority of the UNSC Navy's Office of Naval Intelligence. Ferret teams are tasked with investigating situations or criminal activities that prove threatening to the Unified Earth Government and its United Nations Space Command, and then "fix the problem", perhaps by eliminating targets or rescuing endangered individuals. One such team includes Spartan-IIIs Ash-G099, Olivia-G291, and Mark-G313 led by ONI operative Veta Lopis, a former special inspector for the Gao Ministry of Protection.

Following the Human-Covenant War, ONI feared that knowledge of the illegal and dangerous drugs utilized by the Spartan-IIIs of Gamma Company would become public. Taking measures in an effort to prevent such a leak from occurring, Admiral Margaret Parangosky, CINCONI, ordered that Ash-G099, Olivia-G291, and Mark-G313, at the time serving with Blue Team, be officially listed as killed in action and reassigned. Taking note of the proficiency of Special Inspector Veta Lopis and a bond that had formed between her and Ash, Olivia, and Mark during Operation: JOVIAN WHISTLE in July 2553, ONI formed a Ferret team out of the four, with Lopis leading the team and running the investigations.

List of appearances

• Halo: Last Light (First mentioned)
• Halo: Fractures
  • A Necessary Truth (First appearance)