Raffles: The Amateur Cracksman by E. W. Hornung
I can't remember what I was reading that mentioned Raffles, but clearly something put him on my to-read list. Raffles is a gentleman and a good cricket player. He's also a charming jewel thief. His exploits are written up by, Bunny, his partner in crime who is never quite all in the know.
These are a fun collection of interrelated stories. Raffles is unrepentant but has a lack of seriousness that lets you root for him. The thefts are sometimes clever and Scotland Yard is mostly incompetent, of course....