On their honeymoon trip through Europe, Prudence and Knighton join a small group of travelers to see the triple falls on the river Velino in Italy when tragedy strikes. Their carriage breaks down on a remote road, they are accosted by bandits, and escape only to find one of the travelers dead the next morning in a ravine near the bandits' ambush location. The mystery deepens when they discover the victim is wearing another traveler's cloak. To make matters worse, the inn they are forced to stay in is reputed to be haunted. As Knighton and Pru investigate, they discover the other passengers of the coach were not the strangers they seemed. Revenge, envy, and frustrated love vie as motives, and Knighton is pushed to desperation when Pru is kidnapped. He must use every ounce of logic and intelligence to find the killer and free his wife before there is another death on the road to Rome.