The first season was followed by a Halloween special, broadcast on October 31, 2010, which saw Imelda Staunton added to the main cast.
The second season started broadcasting on May 5, 2011 and ended on June 6.
Filming for the series began at locations around London in October 2008, with plans for the show to be broadcast in 2009. In May 2009, it was confirmed that the series would begin on June 11, although it was later re-scheduled to June 18.