not read it myself but hearing about the rebus ones the other day and thought it might appeal to my elderly grandad for christmas. he's not so active thesedays very sadly and i think likes getting involved in a detective story, figuring it out.
I know he's a big boy but he doesnt like effing and jeffing and if there's lots of rudeybits it'd be inappropriate for me to buy it for him. he's a vicar too!
the odd swearword we can deal with but if it's every other word....
Ian Rankin's Rebus novels are good and you could also try Steven Booth's series of detective novels set in the Peak Districy maybe, or Susan Hill's Simon Serrailler series which is touches on some medicine and religious themes.
What about the Inspector Montalbano books? Kind of a light-hearted Italian equivalent. And nearly a dozen of them.
I am super keen on Dr. Siri Paibourn books (Colin Coterrill). My folks who like crime mysteries are reading them. Too light for my dad, but step-mum (70yo) enjoys. Best read in order, and be mindful that the latest book is much darker than the others.