 Frank Spotnitz and Carter did not have much time to cast this character, but they knew this casting would be important since he intended to be a recurring character.Thompson was chosen according to Spotnitz because he had a very "distinctive look" about him, most notably his face and mouth.After casting him, they told Thompson's agent that Thompson needed a hair cut, because at the start the Alien Bounty Hunter was supposed to be a kind of military pilot who'd been shot down.