A serial killer is someone who murders a number of people over a period of time, normally using the same method again and again.

Some will continue their reign of terror for years, whereas others will murder many victims over a relatively short period of time.
In Series 1 of Crimes That Shook The World, we featured some of the most notorious murderers in history - including Fred and Rosemary West, The Green River Killer and The Phoenix Strangler. Visit the links on the left to find out more about each killer.

Starting on Saturday 13 June, series 2 will reopen the files of other infamous crimes and take a look at the most shocking murder stories from around the world.

Kicking off the series will be the Chessboard Killer, who charted his crimes on a chessboard, filling in 62 of the 64 squares by the time he was caught.

Episode 2 will take a look at the shocking case of the Monster of Florence, who for seventeen years preyed on young couples, committing brutal murder on seven occasions in and around the city.

Find out when to watch on our TV Show Guide.

Watch the trailer for Crimes That Shook The World