Prison Screw, Mr MacKay was a wonderful creation, a true comedic great, sadly, the kind of comedic great that we no longer witness in today's shite comedies. The character was great because of the actor Fulton MacKay's wonderful interpretation of the tough, no nonsense, neurotic Prison Warder. Fulton and Ronnie Barker complemented one another so well and the scenes the duo appeared in together were priceless and are the stuff true comedy legends are made of.
Mackay is a neurotic and tough prison warder whose constant obsession in life is to catch out Fletcher. The rivalry between Fletch and Mackay was a thing of comedy legend. Fletch's sly tactics in misdeeds ranging from fixing boxing matches, stealing pills from the prison Doctor and eggs from the prison farmyard right through to finding new and imaginative ways to stick two fingers up at Mackay and get away with it, were specially designed to get up Mackay's nose. In return, Mackay's frenzied attempts to catch Fletch out, when fruitful, gave Mackay a level of smugness and satisfaction which was only accentuated by Fletch's hostility and skulking.
Mackay was born into a poor family, he was one of 8 children and his father was an unemployed miner. MacKay was formerly a drill Sergeant in the Argyll & Sutherland Highlanders, and he brings the same manner and expectations of discipline to his job at HMP Slade. Mackay's temper is agitated by the constant suspicion he has of Fletch, and his despair at the leniency of his other polar opposite in the series - his optimistic, mild-mannered, kind-hearted prison officer colleague Mr Barrowclough.
Mackay's homeland of Scotland serves as a constant source of entertainment for Fletcher who is constantly on the lookout for an opportunity to antagonise Mackay. In one episode Mackay questions Fletch on whether he felt he was working class. Fletch responds 'I did, until I visited Glasgow. Now I think I'm middle class.'
Mackay's approach to prison officership is perfectly encapsulated in a ranting lecture he delivers to Fletcher and some of the other prisoners on his unexpected return from a period of absence on a training course in the episode, 'Disturbing the Peace.' Strutting back and forth in front of them, he takes great delight in yelling that "There's going to be a new regime here, based not on lenience and laxity but on discipline, hard work and blind, unquestioning obedience. Feet will not touch the floor. Lives will be made a misery. I am back, and I am in charge here." Despite this speech, every single inmate, including Fletch and Godber greet his return with a rendition of "For he's a jolly good fellow.". Possibly because it meant the end of the much more severe Mr. Wainwright, who even went as far as stepping on Fletcher's hand when he got his shoes wet.
He also displays his contempt for the prison occupants in an exchange with Fletcher when the latter protests about the infringement of his rights: "rights are a privilege that you forfeit when you choose to transgress the law".
On another occasion he remonstrates with Barrowclough. Mackay: "They're criminals, man!" Barrowclough: "Ah yes but they're also human beings." Mackay: "All right. But criminal human beings!
Despite their rivalry, Fletcher and Mackay can occasionally get along. This is seen in the Christmas special "No Way Out," after Fletcher, while attempting to reveal a false tunnel to Mr. Mackay when the inmates were planning an escape, landed up in the infirmary. A triumphant and tipsy Mackay visits him there and offers Fletcher a (slightly used) bottle of liquor as a Christmas present, and for information regarding the disposal of the dirt from the tunnel. Fletcher responds by informing Mackay the inmates had dug another tunnel and deposited the dirt from the first tunnel down that one!
He appeared in the first episode of spin-off series "Going Straight" having been retired out of the prison service. He and Fletcher share a few drinks on the Fletcher's train home, and although dismissive of Fletcher's plans to go straight, wishes him luck in the future after he gets him out of unknowingly smuggling goods.