Muller was in prison for the infamous Vallejo kidnapping when he implicated himself in unsolved attacks in Palo Alto and Mountain View, prompting a renewed investigation and DNA analysis.

Matthew Muller, who is currently serving a 40-year sentence for the kidnapping of Denise Huskins, pled guilty Friday in Santa Clara County court to new charges stemming from a pair of home invasion sexual assaults.

The case Muller is most known for, as shown in Netflix’s ‘American Nightmare,' happened in Vallejo in March 2015 and involved the kidnapping of Denise Huskins.

"American Nightmare" victims Denise Huskins and Aaron Quinn worked with two small-town law enforcement officials to get kidnapper Matthew Muller to confess to more cold case crimes.

Kidnapping and rape survivor Denise Huskins spoke to reporters in Seaside on Tuesday about how she helped investigators find more victims who were allegedly targeted by Matthew Muller. The Muller case regained traction after it was detailed in a popular Netflix documentary,

Matthew Muller was convicted of kidnapping and sexual assault in a 2015 case in which Vallejo police initially accused the victim and her boyfriend of making up the story of her abduction. He pleaded guilty this week in two additional cases.

Muller admitted he committed two home invasions in 2009--one in Palo Alto and one in Mountain View. During those home invasions, Muller held captive, interrogated and threatened to rape two women.

Matthew Muller pleads guilty to invading woman's homes in Mountain View and Palo Alto in 2009, six years before kidnapping Denise Huskins in Vallejo in ordeal initially deemed a hoax.