This episode was also released under the title "In the Line of Duty".
Mark Bonnar (Dryden) & Henry Pettigrew (Cole) also worked together on New Blood (2016) as Peter Mayhew & Bruce Lockwood respectively, as well as on two episodes of Shetland (2013) as Duncan Hunter & Iain Redford respectively.
Martin Compston (Steve Arnott) & Niall Macgregor (Rich) also worked together on Monarch of the Glen (2000) as Ewan Brodie & Malcolm McRae respectively.