California prosecutors have filed new charges against a convicted kidnapper and rapist in connection with a 2015 abduction and ransom case with three victims in the Bay Area that cops had never been told had happened until he confessed, according to authorities.

Matthew Muller, 47, is serving a 40-year sentence for the kidnap and rape of a Vallejo woman in 2015. Her abduction was initially thought to be a hoax, cynically dubbed the “Gone Girl” kidnapping after the book and movie.

In the new case, which was not reported to police at the time, Muller allegedly kidnapped two unidentified men and a woman in San Ramon and held them hostage until one of them paid “tens of thousands of dollars” in ransom to release all three.

“The trauma of crime can have lasting effects that some people endure for their entire lives – whether the crime is reported or not,” Becton said. “Muller committed serious offenses throughout Northern California, and my office will be resolute in seeking justice on behalf of the victims in Contra Costa County.”

In the Vallejo case, Muller broke into a house and drugged a woman and her boyfriend. He tied up the female victim, brought her to a cabin in South Lake Tahoe, and sexually assaulted her. He held her for two days before driving her to Southern California and letting her go.

Fox News’ Stepheny Price contributed to this report.