Career thief Dodger Lane (Peter Sellers) and his two loyal partners "Jelly" Knight (David Lodge) and Lennie Price (Bernard Cribbins in one of his first ever film roles) are serving time together at Huntleigh Prison. However, as prisons go, things are pretty cushy: the gang has no problem sneaking food and other comforts into their cell, the Chief Prison Officer, Jenkins (George Woodbridge), is crooked and on good terms with everyone, and the prison Governor is convinced that the institution is a haven of rehabilitation without any problems, all the while the inmates are keeping up appearances and can do pretty much anything they want when nobody's looking.
As the gang's sentence is nearing its end, Dodger is approached by "Soapy" Stevens (Wilfrid Hyde-White), a con man and former partner of theirs, who proposes a daring but lucrative robbery of a military transport that will be moving a fortune in diamonds belonging to a sultan for a ceremony. He and Dodger come up with a plan for Dodger, Jelly and Lennie to sneak out of the prison the night the transport is happening, just a day before their sentences are done, and then sneak back inside, giving them an iron-clad alibi for the crime. Unfortunately, as they are making preparations, Jenkins retires and the prison gets a new, less lenient CPO: the petty disciplinarian Crout, a.k.a. "Sour" Crout (Lionel Jeffries). With him in the mix, the gang has to get even more creative in executing the plan.
The film also starred Liz Fraser, Irene Handl, and Maurice Denham.
Tropes
- Affably Evil: Most of the main cast are career criminals, but all of them are mostly nice, pleasant people. By contrast, Crout is a total Jerkass.
- The Alibi: The heist plan hinges on Dodger, Jelly and Lennie using their prison sentences as their alibis, getting out of their cell at night, doing the deed and then getting back in before the prison staff can realize they've left.
- And the Adventure Continues: Having lost the diamonds after stealing them, Dodger, Jelly and Lennie are seen infiltrating the sultan's weighing ceremony in the ending, planning another crack at it.
- All for Nothing: The gang nearly get away with the diamonds, but when Lennie hides on the roof of the train, he accidentally drops the bag getting down so it lands in a net used by the mail train.
- Ambiguously Gay: Dodger doesn't seem to care much at all for Ethel, his girlfriend on the outside, despite having almost married her before he was locked up, and takes an opportunity to cop a feel on a well-built male model in the prison art workshop.
- Bad Habits: Soapy mostly gets in and out of the prison to talk to Dodger and the others by disguising himself as a priest visiting to give them guidance.
- Butt-Monkey: Lennie, apparently the youngest member of Dodger's group, tends to get stuck with the worst duties, like checking if a sewer works as an escape route or hiding on top of a moving train.
- The Caper: The story revolves around an elaborate diamond heist.
- Dirty Cop: Jenkins, the CPO at the start of the film, is working with the inmates in their illegalities and on good terms with everyone.
- Distracted by the Sexy: Esther does this twice in the film:
- When she and Lennie's mother are visiting the gang in prison, she publicly pretends to adjust her stocking to distract the visiting room guards while the visitors drop in supplies for the inmates.
- As part of the plan to sneak them back into prison, she pretends her car is broken for the garbage truck drivers by sticking out her rear while pretending to be trying to fix it, luring both of the drivers away so the gang can hide in the car.
- Do Wrong, Right: Lennie comes from a proud family of criminals. When his mother visits him in prison, she berates him for not having managed to escape yet and talks proudly of relatives of his who have done so successfully.
- Establishing Character Moment:
- The opening scene not only sets the mood for the film, but also introduces Dodger, Jelly and Lennie, showing them living comfortably in their cell and having the run of the place. They also almost panic when Jenkins mentions they will have to do a minor bit of work in the quarry, showing how unusual that is.
- Crout's introduction shows him supervising work at another prison quarry, yelling at the inmates, making fun of one for being short and making him carry a big rock when he goes to replace his broken tool.
- Everyone Has Standards: Jenkins actually seems hurt when he realizes that the gold watch Dodger and the others gave him for his retirement was stolen from the governor, which is likely why he didn't bother warning them about what a jerk his replacement would be.
- Hidden in Plain Sight: The inmates use the garden to grow tobacco plants, with Dodger distracting visitors from it by calling the plant by its Latin name.
- Institutional Apparel: Inmates of Huntleigh typically wear overalls most of the time.
- Jail Bake: Lennie's mother seems to do this as a matter of routine. When the gang has cake to celebrate Jenkins' retirement, they find a tool hidden in it out of old habit.
- Karma Houdini Warranty: After staying away from the law for a long time, Soapy gets arrested and sent to Huntleigh in the end.
- Luxury Prison Suite: Downplayed, but Dodger, Jelly and Lennie live pretty comfortably in their cell, being able to buy food from a local grocer and cook breakfast; in the opening scene, the door isn't even locked.
- Prisoner's Work: Crout is seen overseeing work in a prison quarry, and later puts Dodger, Jelly and Lennie to work in Huntleigh's largely unused one.
- Rugged Scar: Jelly is the most physically imposing member of the crew and has a minor scar near one of his eyes.
- Super Gullible: The prison's governor is completely oblivious to how unrestricted the prisoners actually are and has been duped into thinking it successfully reforms them.
- Team Pet: The prison has a "prison cat" named Strangeways who wanders around the place.
- Tyrant Takes the Helm: Crout replaces the retiring Jenkins as Chief Prison Officer, and immediately takes a more controlling approach to running the place.
