The Complete Inspector Grant includes all five of the Inspector Alan Grant Mysteries by Josephine Tey. Josephine Tey - Inspector Alan Grant Mysteries:

The Man in the Queue,
A Shilling for Candles,
To Love and Be Wise,
The Daughter of Time,
The Singing Sands.

Alan Grant, is clever but very ordinary in many ways, save his dogged determination to find the truth. He is kind and fair and worries about whether he has found the right solutions, persevering when others think it is pointless. He uses his position to ensure that justice prevails, often against the odds.