Broadcast as just a one-off, The Security Men was originally commissioned as a four-part series. Filmed in 2011, and copyrighted to that year when broadcast at Easter 2013, it is believed ITV executives were unimpressed with the finished product, cutting it back to one single episode before leaving the production 'on the shelf' for at least 18 months.
An horrific continuity error can be seen in the programme. When the robbers first break into the store, they lever the shutters up just enough to duck underneath. This is seen on the CCTV playback by the guards, before sending one of their number to check. When he then arrives at the scene, the shutter has magically risen another couple of feet allowing him to walk straight underneath it.