London, December 1981. Four Polish builders - Nowak, Banaszak, Kudaj and Wolski - arrive at Heathrow airport.

Nowak, the only English speaker, explains to Immigration that their £1,200 cash is to buy a second-hand car, and promises that they won't seek employment. He denies being a member of Solidarity - his only truthful answer. Actually, they have been hired to renovate a house in Kensington, as their boss knows that Polish workers will cost far less than their English counterparts.

At the local supermarket, Nowak spots a woman shoplifting. When paying for their goods, they see her being led away by the shop supervisor. Nowak goes to a nearby phone box and rings the boss in Warsaw. He pins a picture of his girlfriend Anna on the wall next to his bed.

That Sunday, they go to church. Nowak decides that going out for entertainment is too expensive, so he buys a television for £40, but it quickly breaks down. A neighbour comes round to complain about the noise, but Nowak misunderstands his sarcasm.

A Wrangler clothes display reminds Nowak of Anna, as does one of the sales assistants. On impulse, he shows her the picture of Anna, and asks if she thinks it would make a good publicity poster. The men counter a visit from carol singers with a lusty rendition of their own. They go to the phone box and speak to their loved ones. Nowak is perturbed to hear that Anna has been drinking with the boss.

The following Sunday, Nowak tries to ring Anna again. The operator says that all lines to Poland are suspended due to the military coup. Shocked, Nowak wanders the streets and sees a window full of television screens showing tanks in Warsaw. He tries to reserve a flight, but they're all cancelled. He decides to say nothing to the others. The next day, he borrows a newspaper from a nearby letterbox and moves the television upstairs - he manages to get sound from it at least.

Nowak's bicycle is stolen during a shopping trip, forcing him to carry heavy items back home on foot. He sees Solidarity posters on a nearby wall and tears them down. He resolves to tell the others about the Polish situation, but chickens out at the last minute.

The newly-fitted pipes leak, deluging the house and bringing the ceiling down - but it distracts the Poles from their weekend phone call. Nowak steals a bicycle, repainting it and removing telltale features. Replacing the joints has a severe impact on his budget.

To keep the food supply going, Nowak devises a method of stealing from the supermarket by making a legitimate trip, storing the goods in his bicycle, then returning to stock up on additional goods to the value displayed on the receipt, to be produced in the event of questions. He does this repeatedly, getting bolder on Christmas Eve when he asks for a refund on a turkey that he didn't buy. The manager reluctantly agrees, but is clearly suspicious.

On Christmas Day, Nowak lies in bed listening to the others' revelry. He drinks too much, has a nightmare about Anna, and smashes the television. The next day, he accidentally electrocutes Banaszak - he's fine, but tension is markedly increased. A letter arrives for Kudaj, which Nowak intercepts and burns.

At the supermarket, the supervisor summons the manager, and they ask to see his bicycle. Miraculously, the goods he purchased earlier have been stolen by a homeless man, forcing them to give Nowak the benefit of the doubt.

Nowak refuses to let the men celebrate the New Year in the Polish church. He books flights to Warsaw, which leaves him virtually penniless, and they are enraged when he uses their bonuses to hire a sander. When he retrieves the deposit, they spend it on cheap watches. Nowak shoplifts an expensive scarf for Anna, but is nearly caught.

Finally, the job is finished. They load their luggage into shopping trollies and begin the six hour walk to the airport. Realising that he cannot put it off any longer, Nowak tells them about the situation in Poland. Enraged, they attack him. The trollies roll downhill.