Carlile

In the short story, The Incredible Theft, Carlile was the name of Lord Charles Mayfield's secretary. After dinner, Mayfield had told Carlile to lay out the plans for the new bomber on the study table for Mayfield and Sir George Carrington to peruse. While doing so, Carlile had heard a scream and rushed out to find Leonie, Mrs Vanderlyn's French maid, on the stairs. She claimed she had seen a ghost. Poirot exonerated Carlile from the theft of the plans because he had free access to the plans and could have taken tracings from them at any time. However his brief absence from the study opened up other possibilities for their disappearance.

Portrayals
In the film adaptation of the story as episode 8 of Series 1 of ITV's Agatha Christie's Poirot drama series, Carlile is portrayed by Albert Welling.