A Clue in Wax by Fred M. White

Cheriton, once he had made a start on the new novel, was giving himself almost heart and soul up to it. He worked all the morning, with an interval for lunch and a round of golf afterwards, and then on again in the evening until it was time to dress for dinner and walk across the links to the Holt. So that his visits to the clubhouse and the Dormy House were few and far between. He was rather astonished and somewhat uneasy in his mind when he was putting his clubs in his locker one afternoon to see those two strangers close behind him resuming their coats and changing their shoes. It was still intensely warm and bright, even though it was getting on towards the second week in May, and, overhead, the clouds were gathering ominously as if a thunderstorm was not very far off.

"Looks like a change," the tall man remarked to Cheriton. "We could do with a few showers on the links. The greens are like glass, and even a poor player like myself, begins to fancy his drive on the hard ground."