Nelson Tethers is the lone agent manning the desk in the FBI's Puzzle Research division at the start of Nelson Tethers: Puzzle Agent. At the start of the first game in the series Tethers is attempting to work on a crossword puzzle when he has a strange nightmare. After awaking from the nightmare he is called into action by his superiors to investigate a disturbance at the Scroggins, Minnesota eraser factory, which supplies erasers directly to the White House. Tethers is reluctant at first to take the case as his demeanour when speaking with his superior seems to indicate. Additionally, we find out that this is Tether's first field assignment in quite some time.
Nelson is on his own an excellent puzzle-solver, but chewing gum helps him concentrate. This is represented in-game as part of the hint system. Unfortunately for Agent Tethers, the small town of Scoggins has no fresh chewing gum left. The player will have to collect discarded gum found in the environment to gain access to puzzle hints, meaning that Agent Tethers is willing to chew used gum for the sake of his mission.