Alice Jones

In the novel Dead Man's Folly, Alice Jones is a Police Woman. She is a strong swimmer and helped Inspector Bland to find out if the passengers onboard the Devon Belle would notice if someone was being drowned in a small boat by the boat house at Nasse House.

As a tour boat was passing Nasse House, Alice was in another boat with a colleague near the boathouse. The colleague pushed her into the water as though engaging in horseplay. The colleague then leaned over saying he would not pull her up unless she behaved (enacting a real scenario where the person in the boat actively pushes the person in the water further under the surface). When the act was over Alice got back into the boat.

Inspector Bland on board the Devon Belle noticed that the passengers were too engrossed in listening to the tour guide talk about the various sights especially Gooseacre Rock on the opposite side. So nobody saw Alice and what was happening.