I recently found the Lord Peter Wimsey series of detective/mystery novels. It’s awesome! At least if you like older British detective stories, where everything is very high class (he is a lord after all, though it’s his brother that’s the actual duke), but with a dash of humor.
Lord Peter has this almost Deadpan Snarker -like quality sometimes, but he manages to hide it behind a mask of fancy politeness when he likes. And he is very human, driven to detection because of curiosity, wanting to back out when he realises that someone will probably be hanged because he meddled into things, suffering from flashbacks to the unpleasantness of WWI.
And the side characters are cool as well. Lord Peter’s manservant Bunter is the archetypical servant character, who gets everything done, but also has his own dry sense of humor. The love interest (does not appear in all of the books) is an interesting character on her own, and there is no instant falling in love and getting together. And she does her own bit of detecting as well.
One of the books is set in Oxford University! Peter wears a monocle that works as a magnifying class! The characters actually aged at the same rate the boos were published! The anglophilia in me is just overflowing!
And at least some of the stories have been translated into Finnish. It doesn’t matter too much in which order they’re read, but there might be some casual spoilers. And some of the are perhaps more clearly connected, like Gaudy Nightand Busman’s Honeymoon.