Crewman third class Foster was an operations division United Earth Starfleet officer who served on board Enterprise NX-01 during the 2150s, under Captain Jonathan Archer. In 2153, Foster served as a security guard for the two assimilated Tarkaleans in sickbay which were transported from their freighter. When the Tarkalean male woke up and Doctor Phlox was up to inject him a sedative, Foster tried to help Phlox but was hit and then thrown through the room against a rack by the Tarkalean female.