The producers have admitted that it is hard to film on the streets of London as actors such as Bradley Walsh (famous for his role as Danny Baldwin on Coronation Street (1960)), Jamie Bamber (famous for his role as Lee "Apollo" Adama on Battlestar Galactica (2004)) and Freema Agyeman (famous for her role as Martha Jones on new Doctor Who (2005)) are easily spotted by the public. In fact, in some scenes it is possible to see people in the background stopping what they are doing to see what's going on.