Ecuador, 1980: A flash flood on the Rio Ambato uncovers the bodies of four young girls in shallow graves, and an incident at a street market leads to the capture of Pedro Alonso López, a man who would come to be known as the Monster of the Andes, one of the most horrific and prolific serial killers in history.

Mike and Martin explore this tragic true crime case from South America, examining the shocking background to the crimes, the plight of the victims’ families, and the disturbing final mystery that, even today, casts a long shadow over Ecuador, Colombia and Peru.

This episode contains discussion of murder and sexual assault, which some listeners may find distressing.

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