The crooks in London know how it works. No one carries guns and no one resists the police. Then a new gang appears that go one better. They dress as police and steal from the crooks. This upset's the natural order of the police/criminal relationship and the police and the crooks join forces to catch the IPOs (Impersonating Police Officers), including an armoured car robbery in which the police must help the gangs to set a trap.
| Camera | Ernest Steward | Director of Photography |
| Writing | Ray Galton | Writer |
| Writing | Alan Simpson | Writer |
| Directing | Cliff Owen | Director |
| Editing | Tristam Cones | Editor |
| Writing | John Antrobus | Writer |
| Camera | Ray Hearne | Still Photographer |
