Paul Rousseau was accidentally shot in the head by his best friend and flatmate. When Paul met Mark in the first year of university in the US, they quickly became close. They moved in together, and spent most of the next four years in each other's company. But Paul did not know that Mark had been keeping a collection of guns in his bedroom. In April 2017 one of Mark's guns accidentally went off, the bullet passing through two walls before striking Paul in the head. In the months and years that followed, Paul had to deal not only with his brain injury, but also the devastating impact the event had on his friendship with Mark.Presenter: Shahidha Bari Producer: Rebecca VincentGet in touch: liveslessordinary@bbc.co.uk or WhatsApp: 0044 330 678 2784