As with many of Christie’s other murder-mystery novels, And Then There Were None is marked by a suspenseful tone, as a series of seemingly inexplicable deaths on a remote island are revealed to be the work of a skillful and cunning murderer. This tense, suspenseful tone is apparent in the narrator’s description of the mansion and its guests on the evening of the murder of General John Gordon MacArthur:
If this had been an old house, with creaking wood, and dark shadows, and heavily panelled walls, there might have been an eerie feeling. But this house was the essence of modernity. There were no dark corners—no possible sliding panels—it was flooded with electric light—everything was new and bright and shining. There was nothing hidden in this house, nothing concealed. It had no atmosphere about it. Somehow, that was the most frightening thing of all….
They exchanged good-nights on the upper landing. Each of them went into his or her own room, and each of them automatically, almost without conscious thought, locked the door….
The narrator highlights the surprising modernity of the mansion, which seems to admit no “eerie feeling” in the manner of a haunted house. However, the “new and bright and shining” nature of the house actually makes it all the more “frightening” to its inhabitants, as they cannot discern the killer’s methods in this unlikely and well-lit environment. Although most guests still speak to each other politely at this point in the novel, their lack of trust and the tense atmosphere is emphasized by the fact that each of them “locked the door” for their own protection.