The play strikes one as more comic, at least in the first Act, than it is played here under James Grieve’s direction. More Thin Blue Line and less Z Cars might have helped. James Graham’s writing, his focus on convention and protocol, should guide proceedings, and it does, at least to start. The opening scene goes a long way in the right direction, although the characters, all police, could afford to be more stereotypically quirky and fussy. Harry Melling, a supple and intriguing actor, always reliable, does the very best work here.