Norman Stanley Fletcher is caught after commiting a crime. He is sentenced to serve five years in Slade Prison. The trip to the prison ends up being an eventful one.
Lenny Godber is new to Slade Prison. Thankfully, old hand Norman Stanley Fletcher is around to share his knowledge with Godber. The first lesson? Getting into the good books of the Governor.
Ives wants to become part of Fletcher's gambling group, which Mackay is determined to put a stop too. After Fletcher rejects Ives, things start to go badly for Fletcher, or so it seems.
Fletch attempts to explain to Godber the best ways to cope with prison life.
Fletcher and Godber get a day out of the prison when they are required to dig some ditches. When Mackay leaves Mr. Barrowclough in charge, Fletcher and Godber end up taking advantage of him.
After falling out with the prison governor, Fletcher has lost his job in the library. He comes up a plan with McLaren which he hopes will make his look good again. It ends up involving a trip to the prison roof, which for an acrophobic Fletcher, causes problems.
Fletcher ready a love letter for the illiterate Bunny that he has received and attempts to offer him some advise regarding the fairer sex. Fletcher's daughter pays him a visit with some news from back home.
Fletcher works out there is a thief among the prisoners after his pineapple chunks go missing from his cell.
Godber girlfriend, Denise sends him a letter ending their relationship. Fletcher's daughter Ingrid ends up doing a better job of consoling Godber than Fletcher does.
The prisoners are happy with the apparent departure of Mackay. The happiness doesn't last long though after they meet his replacement an old 'acquaintance' of Fletcher called 'Napper' Wainwright. Barrowclough is sent to the prison farm because Napper believes that he is too soft on the inmates. The inmates end up staging a riot to get him Barrowclough back and humiliate Wainwright at the same time.
After falling off a ladder Fletcher breaks his ankle. Whilst staying in the hospital wing, he learns that Norris has cheated Blanco out of all his possessions. Godber, Fletcher and Blanco manage to trick Norris who is about to be released after servicing his sentence in to believing that Blanco has a case full of buried money waiting to be dug up.
Godber is preparing to represent the prison wing in a boxing tournament. Harry Grout wants Fletcher's help in persuading Godber to take a dive. Godber isn't not happy with the idea as he has already agreed to take a dive for someone else.
Fletcher's plans for a quiet Saturday afternoon in his cell are ruined by constant visits.
All Fletcher wants is a quiet Christmas, but one of Groutie's friends is building a tunnel out of Slade Prison, the tunneling noises being drowned out by the prison Choir. Anxious to keep his nose clean, Fletch is desperate to get into the prison hospital before the escape plot is discovered, so he conjures up an injured right knee - or is it the left knee? As fate would have it, Groutie is determined that Fletch should be at the centre of things, even going so far as to pick up a blank passport on his day out of the prison to get his injured right - or should that be left? - knee X-rayed.
Barrowclough and Mackay discover Fletch is cooking up some home brew, and the crafty con seems certain to spend Christmas in solitary confinement.
Some pills are stolen from the surgery by Harris and when Mackay searches him he manages to get rid of them. Fletcher is told by Grout to make sure they are replaced so that his pill-peddling racket will remain uncovered.
Fletcher's new cellmate ends up being the judge who sent him to prison.
After Judge Rawley's watch is stolen, Harris is the only suspect. A kangaroo court is set up as Harris is put on trial.
After Blanco is given parole, he refuses the chance to be released. He demands that he be pardoned as he never killed his wife and leave prison with his name cleared.
Godber is trying to gain an O - Level in history. Fletcher thinks it is a waste of time but he still wants to help Godber pass his exam. Fletcher, Warren and McLaren decide to steal the exam paper so that Godber will know the questions in advance. The problem is they send in Warren to steal the exam paper bu he can not read.
Godber ends up getting involved in a brawl just before he is due to face the Parole Board which could damage his chances of being released from prison early.