Advanced Paramedic Kev is dispatched to a cardiac arrest. There is brief hope when they get a pulse back, but the patient needs to be urgently transferred to hospital, and a van is blocking the ambulance’s path and refusing to move. Gary and Fabio are dispatched to a patient who has fainted at Oxford Circus underground station, but whilst on scene, Extinction Rebellion protesters flood the area and block the roads. The next day, as MPs sit during the weekend for an important vote in Parliament, the team in control is taken by surprise when there's a problem nobody had foreseen - the entire computer system used to respond to 999 calls crashes. The team is forced to make an urgent switch from computers to pen, paper and map books, answering calls and taking down the information by hand before dispatchers radio the crews and direct them to the most serious cases.