An ordinary British family contends with the hopes, anxieties and joys of an uncertain future in this six-part limited series that begins in 2019 and propels the characters 15 years forward into an unstable world. Daniel (the youngest brother) is getting married to Ralph, Stephen (the oldest brother) and Celeste (his wife) worry about their two daughters, Edith (the oldest sister) is engaged in one humanitarian cause after another, and Rosie (the youngest sister) is a single mother with spina bifida raising one boy, and about to give birth to a second. Presiding over them is Gran, the imperious Muriel.
In 2027, voting is made universally mandatory, the coalition government collapses and Viv Rook becomes the Prime Minister. Stephen has a bad reaction to a drug experiment that he has secretly participated in for money. He calls Elaine to pick him up but the clinic accidentally calls Celeste too and the three have an awkward meeting at his bedside. Arriving home, Celeste coldly confronts Stephen about the affair on a conference call with the whole family. Muriel angrily demands that he leave her house and he moves in with Elaine, who is less welcoming than Stephen expected. Rosie begins a mobile catering business with her new boyfriend, Jonjo. Edith warns him that she is suspicious of his intentions toward Rosie's young sons and will be watchful. Viktor's immigration status in Spain is again uncertain and, fearful that he will be repatriated to Ukraine, Daniel decides he has no choice but to bring him to the UK illegally. Their trip is a chaotic nightmare, first when hiding in a tourist bus is unsuccessful and then when they are ripped off both for money and Daniel's passport while attempting to buy forged documents. Finally they try sailing in an overcrowded boat from France. Half a mile off the British coast, the boat sinks. Daniel and most of the other migrants drown. Viktor survives and returns to Daniel's apartment in Manchester alone. He is stunned and robotic as he phones the family with the news, and they rush to the house, but Viktor won't answer the door.