David is into science and UFO's. He is well known for his knowledge of flora and fauna and his sense of direction. He is a main character of the first series, but then becomes the plot in the second. He is seen at the beginning of the third series.
He is close friends with Harry but can get easily agitated and wants everything his way. This often caused tension with the rest of the group, and several characters have frequent arguments with or about him. He begins a relationship with Sarah early in the first series through their interest in UFOs. He tries hard to get along with Simon, but David is unsuccessful until the third series. They never become close friends. David does survive as he was sent by the aliens to Falkirk before the rest of the group and did not contract the red eye virus.