Flamboyant and outspoken, Michael Armstrong worked a great deal but was visible far less than he perhaps should have been. While House of the Long Shadows did not mark the end of his writing career, it did mark his progress into the position of uncredited script doctor, a position he held on the abominable Lifeforce. He moved to the United States in 1984 in an attempt to regenerate his career but was by and large unsuccessful, despite working for then-successful producer Sandy Howard, who commissioned several scripts and treatments. In 1985 he returned to England and vanished completely from sight.
As a director he was responsible for Burn, Witch, Burn and Horror House (which he also wrote). As an actor he starred in Eskimo Nell (as well as writing it) and appeared in The Sex Thief. He turned up as an actor in a variety of tiny parts, many uncredited, many of them on-stage.
