Concerned 999 callers report an HGV swerving all over the M6, so PCs Jamie Barlow and Amy Hollis team up to search for the vehicle in question. When they finally catch up with the driver, they discover the awful truth behind his dangerous driving. On the M56, two trucks have collided near Cheshire Oaks, with reports that one of the drivers may have suffered a heart attack, so Inspector Anton Sullivan races to the scene of the crash to find out exactly what happened