Bass was a mercenary and a member of Max Stafford's private military team. In 2004, Stafford's team was hired by Charles Bishop Weyland to accompany a Weyland Industries expedition to Bouvetøya, Antarctica. The expedition's objective was to investigate an ancient Pyramid buried beneath the ice there, with Stafford's team present to provide security. The Pyramid was discovered to be a Yautja temple and hunting ground where the Predators would breed Xenomorphs for use in their Hunts, and the expedition soon became caught up in the battle between the two species.
Bass was killed by Scar when his team was ambushed by the Predators.
When Stone was silently dispatched by the Yautja, Bass and the others with him were alerted to the danger by the dead man's weapon clattering to the floor. As he scanned the area, Bass suddenly noticed one of the many Yautja statues in the room was in fact a real creature, but this realization came to him too late — Scar hurled his Combistick at the mercenary, impaling him and triggering a firefight. After the shifting walls of the pyramid separated several surviving members of the expedition from the Predators, Stafford mourned Bass' death, laying responsibility for it on Weyland's shoulders.
Like the majority of Stafford's mercenaries, Bass armed himself with a Heckler & Koch G36C carbine fitted with a flashlight and lime green laser sight during the expedition to Bouvet Island.