Johnson (The Red Signal)

In the short story The Red Signal, Johnson is the manservant of Sir Alington West. He overhears an argument between Sir Alington and his nephew Dermot West. When shortly thereafter, Sir Alington is killed, Johnson's account of events makes Dermot the prime suspect in the murder.

Portrayals
In the episode The Red Signal of The Agatha Christie Hour, a TV film adaptation of the story, the part of Johnson is played by Michael Denison. His role is largely similar to that in the original story but he has a lot more lines and screen time. He is shown at the beginning helping Sir Alington dress for dinner. Later, he is shown being interviewed by Inspector Verall at the scene of crime where he narrates what he overhead. This scene is also used for Johnson to provide background information on Sir Alington and Dermot--how Dermot is Sir Alington's nephew and his only living relative and that they are quite close.