Mark Elgin

Mark Elgin was the public relations officer for the Global Chemicals oil refinery at Llanfairfach.

Biography
Elgin began to question Stevens after Ted Hughes and Dai Evans were killed.

When Ralph Fell began acting strangely, Elgin followed him into a pumping room, and stopped him from killing the Third Doctor and Jo Grant by pumping watse into the shaft they were in. He then helped the Doctor and Jo exit the facility without being seen.

Stevens began to see Elgin as a liability after he threatened to expose Global Chemicals, and had him hypnotised by BOSS. (TV: The Green Death)

Behind the scenes

 * Before the studio recording for episode five, the actor playing Elgin, Tony Adams, fell seriously ill and was rushed to hospital. The part was hastily rewritten for a new character named James, played by Roy Skelton. Elgin was abruptly dropped from the story — not to be seen or referred to again — and presumably survived. (DWM 320, INFO: The Green Death)
 * Elgin's first name is not given on-screen, only in the novelisation.