This sign had me at hello. But was I in the San Francisco of The Maltese Falcon or in Paris? It took me a minute but it all came back. I was on rue du Louvre, the same street where Aimée Leduc, heroine of mystery writer Cara Black's Paris-based thrillers, has her office. Duluc/Leduc? Coincidence? I think not.
If you haven't picked up one of Black's books, I'd definitely recommend them. They are fun, fast reads with lots of references to all kinds of famous and out-of-the-way places in Paris, plus plenty of car explosions, lock picking, and general detective novel shenanigans. The first one I read was Murder in Belleville (because it was in a stack of books gifted to me by someone leaving Paris) but I think it's probably better to start at the beginning of the Leduc saga with Murder in the Marais.