A Pale Moon Was Rising

A murder mystery set in Ireland during WW2
The war in Europe is turning. But Ireland is still under enormous pressure from the lack of basic essentials. And the constant threat that Germany could use it as a back door to attack Great Britain.
So when an unidentified submarine is spotted in Tralee Bay on the west coast the alarms sound.
Next morning the body of a young man with fatal head injuries is found in the River Lee. He’s wearing a distinctive silver ring.
Garda Eamon Foley traces the ring to Paudy Daly, the oldest son of the notorious Mixer Daly who has been missing for over nine months.
So who is the mysterious dead man, and why is he wearing Paudy’s ring?
Then Garda Foley learns that the last time Paudy Daly was seen alive, he was on his way to rob the home of a reputable pig-breeder.