John Dickson Carr 
To Wake The Dead [EPUB ebook] 

Christopher Kent, worth a quarter of a million pounds yet without a penny in his pocket, stands hungrily in Piccadilly one snowy morning, looking up at the huge hotel, when a piece of card bearing a number floats down to him. He enters and is served with breakfast, giving the waiter the room number. Then an unlucky chance compels him to go up to room 707. Inside a woman lies murdered in a trunk. Kent needs to prove his innocence fast, and calls in Dr Gideon Fell to investigate — but there’s been another murder, and Dr Fell must figure out what connects them in order to find the guilty party.