Jodie Comer and Stephen Graham had previously worked together in the first episode of Good Cop (2012). While filming that episode, Graham was so impressed by Comer's performance that he proceeded to call his agent Jane Epstein while on the set. Following Graham's recommendation, Epstein later met with Comer, who was a relatively unknown actress at the time. She became her agent, which led to a boost in Comer's acting career and also to a close friendship between both actors.
Features one unbroken take with a length of about 26 minutes, which took two attempts to get right. Jodie Comer admitted that, while she was filming the first one, she had a moment in which she was in her own head, but she was sure that they had wrapped the scene. Once the first take was completed, to her surprise, director Marc Munden asked for one more. The second attempt, which was eventually used, was demanding for Comer, and she said that there was a moment they never would have gotten during the first take.
In order to depict the care home workers realistically, real workers were consulted about their own experiences during the pandemic. They later praised how accurately they have been represented in the film.
Jack Thorne initially wanted to write a story that focused on the different aspects of care homes and care home politics, until producer George Faber talked him out of it. He admitted that he was scared of writing about COVID-19, but he realized how important the topic was the more he read about it.
The radio announcements reporting about the COVID-19 outbreak in England were taken from actual recordings of that time.