Outsiders

S3, E7: MI5 is alarmed when the death of a young primary school teacher brings the number of paracetamol-related fatalities to 9, with 11 more victims in a serious condition listed across Britain. It transpires different brands of pills have been laced with menazorphine, which would alter its effect to like drinking acid. Someone on the outside has hacked into the manufacturer’s computer systems and deliberately caused this lethal cocktail to occur.