Taken at the Flood

Gordon Cloade marries a young widow, but within days he is killed by a gas explosion in his home, leaving no will, so that his fortune all goes to the new Mrs Cloade. But then Poirot has a visit from a member of the family who claims she has information from the spirit world that the rich Mrs Cloade's first husband is still alive, so that she is still Mrs Underhay. Poirot is asked to find the missing Underhay, with supernatural guidance.