Collects Halo: Blood Line #1-5. Based on the Best-Selling X-Box game! Blood Line is the top-secret unconventional warfare unit of the United Nations Space Command's Office of Naval Intelligence, engaging in sabotage and assassination missions deep inside Covenant space. But when this quartet of super-soldiers is shot down over a desolate moon along with a Covenant crusier, humans and aliens will have to forge an uneasy alliance against a common foe before an eons-old threat destroys them both!