Mr. Flexen was beginning, somewhat gloomily, to think it probable that the problem of the death of Lord Loudwater would have to be set among the unsolved problems which have at different times baffled the police. Then, before he had quite lost hope, there came a letter from Mr. Carrington. It ran:
"Dear Mr. Flexen,
"I received this morning a letter from Mrs. Marshall, of 3, Laburnum Terrace, Low Wycombe, asking me, as the agent of the present Lord Loudwater, to have some repairs made to the house in which she is his lordship's tenant. We have never handled this property; we did not even know that it belonged to the late Lord Loudwater. If you can find the man who managed it for him, he may be able to give you the information you want.
"Yours faithfully,
"C.R.W. Carrington."
In ten minutes Mr. Flexen was at 3, Laburnum Terrace; in a quarter of an hour he had learned that Mrs. Marshall had paid her rent to Mr. Shepherd, of 9, Bolton Street, Low Wycombe; in twenty minutes he had learned from Mrs. Shepherd that her husband was in Mesopotamia, and that she had not heard from him for two months. In half an hour from the time he read Mr. Carrington's letter he was in the train on his way to London. To get in
