The Yellow Room — Mary Roberts Rinehart

A corpse - somewhat charred around the edges - has been discovered in the linen closet of the Spencers' fabulous Maine retreat. No one has a clue as to who she is or how she got there. Certainly not Carol Spencer, who has just arrived to open up her isolated family house for the summer.

Unfortunately, Carol seems to be the prime suspect, judging from the questions the police are asking. She has one advantage over the police: she knows she didn't do it. But now the servants have disappeared, all the telephones have been removed, and, as night rapidly falls, a dangerous killer is closer than she thinks....