The adult students at a school for the blind remain blissfully unaware when a small group of terrorists murder their director and infiltrate the building with the intention of assassinating a passing head of state. One of the students - Sally - begins to notice some odd things about the "plumbers" who have moved in upstairs and tries unsuccessfully to convince her fellow students that something suspicious is going on. Her alarm is further increased when she begins to notice the conspicuous absence of the director Mr Mullard, and even believes she has heard someone impersonating him. Eventually the truth is revealed, and the seemingly helpless students find that they are far more capable and resourceful than they had realised...
WRITTEN BY: Terence Feely based on a story by Brian Clemens
DIRECTED BY: Shaun O'Riordan
PRODUCED BY: John Sichel
MAIN CAST: Peter Vaughan (Anderson), Dennis Waterman (Frank), William Marlowe (Jeffries), Sinead Cusack (Sally), Leslie Schofield (Moore), David Jackson (Martin), Michael Lees (George Mullard), Alun Armstrong (Mike), Colin McCormack (Peter), Catherine Chase (Jenny), Angela Walker (Pat), David Sands (Tom)