Ross and John put their armed-response training to the test when they tackle a suspected gunman, while teams are called out to deal with the results of dangerous driving after a person parks on a roundabout and a pedestrian is crushed under a car. Elsewhere, officers raid a cannabis farm, a Reliant Robin is bid a fiery farewell, and Phil finds out what happens when the driver of a Subaru Impreza decides to take on an HGV