When a stationary car is struck by an oncoming lorry at a very dangerous hairpin bend known as Dyke's Corner and the driver killed it seems an obvious accident. However, MacDonald's methodical investigations reveal it was in fact a cleverly contrived murder.
“We’ve taken the wrong fork. There’s a double hairpin bend somewhere.” There was! Immediately in front of them a car was drawn up on the opposite side of the road. As they swung round the wicked curve headlights blazed full at them, blinding them both. A lorry had drawn out to pass the standing car and was coming at them like a battle cruiser. They sensed the rending, tearing scream of metal as the lorry hit them, and darkness came down on them. In that threefold crash it was the occupant of the stationary car who was found dead. Out of the details of a commonplace accident Inspector Macdonald relentlessly builds up the most amazing elucidation of a murder mystery—a case devised with all E. C. R. Lorac’s customary brilliance.