- [talking about criminals and CID officers who drank in the same pubs]
- Barry Phillips: They'd send a drink across and we'd send a drink back. They were a different type of villain in those days, and they accepted that if they were arrested that was just part of their job. They were personable people, and when you get them socially they're personable people, as are CID officers and Squad officers. But the line is drawn: they go to work to commit armed crime and our job's to nick them.
- [the Metropolitan Police took Ian Kennedy-Martin, creator of The Sweeney, to meet some Flying Squad officers]
- Ian Kennedy-Martin: There was a lot of drinking with policemen one night. We went down to a pub in Fulham, and there were about eight people round a table, eight guys all drinking. And only afterwards I heard that three of them were villains, known quantities, and the other five were policemen. And you couldn't tell the difference.
- [talking about the contribution of stunt arranger Peter Brayham, who had knowledge of the criminal world, to the opening sequence of "Regan", the pilot of "The Sweeney"]
- Tom Clegg: Because of Peter's background, he knew a lot about the villains and he knew a lot of characters. He introduced me to quite a lot. I asked him "What would you do, as a villain, if they caught a cop spying on them? How would they have dealt with him?" And he said "They'd have thrown him out the window." So I said "Right, we'll do that."
- [talking about her scene in "Hard Men" when she is in bed with Regan, wearing only a German tin hat]
- Janet Ellis: I think I probably was more nervous than I admitted. But because it was only my second or third job, there was a real sense of "I just want to do this right, whatever it happens to be". If it had been abseiling down the wall it might have felt much the same as lying in bed with John Thaw without a top on, although with hindsight I can see there's a difference!
- [Bill Westley, First Assistant Director, kept the cast and crew in their places]
- David Wickes: Billy didn't stand any nonsense from anybody. If you said "Right! Cut! Print!", Billy would say "Right! Puppets, back in your box!"
- Bill Westley: [referring to the actors] Get the puppets back in the box before someone treads on them.
- Dennis Waterman: [laughing ironically] We were treated with the utmost respect.
- [talking about the Red Cow pub, opposite Colet Court, where the cast and crew used to drink after finishing filming for the day]
- Tom Clegg: It was not a nice pub, but it was home.
- David Wickes: The Red Cow across the street was the local villains' pub. And the local CID used to go and drink there with the villains. And then when they realised that we were across the street, making The Sweeney of all things, the villains used to say "Eh, come over 'ere. Right, that wages van would never, not never, in a million years have gone down that street." And then the police would say "Oh no, C11 wouldn't have allowed that. He'd have had to fill in a form first." and "I tell you how he'd have done it. He wouldn't have answered the phone." And that would go in. And this is how we got a lot of stuff from them.
- Narrator: Whichever side of the law The Sweeney's sources stood, their input meant that the series' realism was second to none.