From Halopedia, the Halo wiki
In 2552, Wilkins was stationed aboard the UNSC Pillar of Autumn and saw action at Fall of Reach. During the Battle of Installation 04 he led a squad of five Marines to guard a Bumblebee for the Pillar of Autumn's command crew. Although three Marines were lost, Wilkins survived.
During the descent and jump to Installation 04, Captain Jacob Keyes borrowed Wilkins' M6D pistol to kill Isna 'Nosolee, the Prophet's employed Ossoona. 'Nosolee had stowed aboard the pod but was noticed by Keyes even through the Active Camouflage.
Once on the ground, the pod's survivors were eventually captured by the Covenant after being betrayed by Ensign Ellen Dowski. The Covenant were only interested in taking Keyes prisoner. The remainder of the bridge crew were killed. Wilkins and his marines were gunned down before any of them could react.
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