Whilst out cycling one night, the S.H'ers noticed that some clever sort seems to have a key to the bus stop advertising boards.
As all of the police recruitment adverts in the east end seem to have a rather more sinister shadow added. We can only assume that the cunning pranksters simply cut out a cardboard cut out and then slipped it in behind the Police posters.
However they managed it, the effect was quite striking, and shows the police in somewhat of a more honest light. The beauty being that the adverts look normal in daylight, and it's only when the night draws in and the backlighting is switched on that they appear.