The Heckler & Kock USP is a pistol chambered to fire the .45 ACP round.
After he learned that there was a traitor who had hacked the Anomaly Detection Device, Nick Cutter waited in a church after triggering a false alarm. When Jenny Lewis arrived on scene, he pulled out his two-tone USP, and held her at gunpoint. He nearly got them both killed but ended up standing down after she revealed that she was sent by Oliver Leek.
Helen Cutter was attempting to infiltrate the Anomaly Research Centre, and to do so, she sent in a Cleaner Clone after arming him with a USP. He made it in, and had gotten into Nick Cutter's locker, attempting to steal an article of clothing. However, he was confronted by Captain Becker, who ended up shooting and killing the Clone after he refused to lower his USP.
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