Killer Kings

Takes a look at Britain's serial killer monarch who is estimated to have executed between 57,000 to 70,000 people during his 36-year-reign, including friends, advisors, clergy, old people, children, and two of his wives.

Caligula earned a brutal reputation despite ruling for only four years, from AD 37 to 41. His reign began with policies such as cutting taxes and pardoning exiles, and historians debate whether syphilis, epilepsy or mental illness changed him.

King John I, infamous for his cruel reputation in medieval times, became the inspiration for the notorious antagonist in the legendary Robin Hood tales.

Tells the story of Ivan IV Vasilyevich, known as Ivan the Terrible, Russia's first tsar. Initially hailed as formidable, his reign from 1533 to 1584 ended with a reputation that matched the modern meaning of his infamous moniker.

Explores the lives of six enigmatic kings who have left their mark on the world, uncovering haunting factors and new evidence that could lead to fresh verdicts for these formidable men.