Cases in which people have murdered relatives, including a look at whether Philip Austin, who killed his wife and two children. Officers determine whether he planned his crimes or acted on impulse.

Criminal psychologist Laura Richards examines why a man raped his wife at knifepoint and killed his four-year-old son.

The story of a man from Lancashire who set fire to his home, killing himself as well as his wife and daughters.

In 1995 Glasgow couple Darren and Frances Jenkinson suffered a terrible tragedy when their 2 month-old son Aaron died of a rare congenital heart defect. Or at least thats what the post-mortem concluded. Four years later, after undergoing fertility treatment, Darren and Frances managed to conceive again. But aged just 3 weeks, second son Jacob died in exactly the same circumstances. Suspicious hospital staff alerted the police to this unlikely coincidence, and detectives then unearthed disturbing signs that Darren might be responsible...

Criminal psychologist Laura Richards introduces the case of Andre Genestin, who murdered his wife after she confronted him about his mistress.