The building in Hemel Hempstead that was used as Henry Crabbe's restaurant was a florist at the time of filming but has now become a restaurant named "Pie in the Sky" in real life.
Season 1-5 title openings show a library shelf with various cooking books mixed in with police training books. A hand pulls out a book and reveals the main character (DCI Harry Crabbe)looking back at him straight on like he is spying on him. This was slightly changed in seasons 2-5 with Crabbe showing a left profile and turning his head and staring out of the missing book slot.