We walked to the Serpentine taking pictures on the way. The band were in the process of removing a coat of arms from above a shop doorway when a couple of special duty police introduced themselves.
Det. Sgt (?): “Do you know what this is?”
*flashes an official looking pair of cards in a plastic wallet*
John: “Yes. It’s a British Rail season ticket!”
Det. Sgt (?): “The other one, smart arse.”