How Twin Sister Playboy Playmates Got Mixed Up In Murder

What started as a three-way relationship between twin sisters and Playboy mogul Hugh Hefner would later end in betrayal followed by the murders of two best friends.

Hefner was newly single in 1998 when he met 22-year-old siblings Sandy and Mandy Bentley at a Los Angeles nightclub. He was immediately smitten. The three began to spend more and more time together until eventually the sisters moved into Hef’s mansion.

“It was definitely a strange gimmick to be dating two twin sisters at the same time,” recalls former Playboy model Holly Madison, who also used to date Hefner. “I don’t know how seriously people took that, but it was definitely controversial. It was definitely something that got a lot of attention.”

The Bentley twins were living the highlife, and they became famous after making their debut together in the May 2000 issue of Playboy. But behind the mansion’s closed doors, the pair were required to follow Hefner’s strict rules, including his demand they not date anybody else. “There was definitely a streak of possessiveness,” Madison recalls. “You’re being watched all the time, whether you realize it or not.”

According to Madison, one of the worst things one of Hefner’s girlfriends could ever do was to be seen with another man. Despite Hef’s aversion to competition, in 1999, Sandy met wealthy highroller Mark Yagalla in Las Vegas. The two secretly began dating, and their relationship “took off like a house on fire,” according to Yagalla’s lawyer, Brian Bieber.

Yagalla spoiled Sandy, lavishing more money and gifts on her than Hefner ever did. “The understanding was it had to be kept quiet,” Bieber says.

According to the attorney, his client didn’t care about Hefner and became completely “focused on and obsessed with” Sandy Bentley.

Sandy and Yagalla’s secret relationship blossomed until one day the pair were caught by one of Hefner’s friends while out in Las Vegas. “Hef, when he found out, was very not only hurt, but pissed off, angry,” says Stacy Burke, another of the publisher’s former girlfriends.

As a result, in the fall of 2000, Sandy and her sister Mandy ended their relationship with Hefner and moved out of the Playboy mansion.

Sandy continued to date Yagalla. He, in turn, lavished her with gifts, including pricey jewels. “But Mark’s business became your classic Ponzi scheme,” Bieber says of his client. “The bulk of it was going to fund his lifestyle.”

Yagalla eventually was arrested, convicted of securities fraud, and sentenced to serve five years in prison. He was also ordered to repay his investors $30 million. The feds then came after Sandy, who was unaware the estimated $7 million Yagalla spent on her was stolen, and demanded she give up her prized gifts.

Sandy claimed to investigators that some of her most expensive jewelry had been stolen before Yagalla’s arrest. Without proof to the contrary, the case went cold.

After her disgraced investment whiz boyfriend’s arrest, Sandy immediately dropped him and moved on to Michael Tardio, a Los Angeles part-time model and doorman. The pair appeared to enjoy a genuine, non-transactional relationship, according to some who knew the couple.

Their story, however, would end in tragedy. On Sept. 2, 2002, around one year after Yagalla’s arrest, a vehicle was found in flames in North Hollywood. “There were two bodies in the passenger seat of this Mercedes SUV,” recalls Bill Cox, a former detective with the LAPD.

Both victims, later identified as Sandy’s new boyfriend, Tardio, and his best friend, Chris Monson, had been shot in the back of the head. Sandy told investigators she had last seen the pair the evening before they were found dead. According to Sandy, Tardio gave her a phone number and told her that if something ever happened to him to call a man named Michael Jacobs. “That was all she knew,” Cox says. “She didn’t know why they ended up dead.”

Weeks after the grisly murders, on Sept. 27, 2002, police obtained this Jacobs’ cell phone records, which indicated he had been in contact with Tardio the night of the killings. During questioning, Jacobs admitted he knew the victims, but he claimed he was with his girlfriend in Woodland Hills when the burning SUV was found.

One of Tardio’s coworkers helped break the case wide open. According to the colleague, in early 2001, Tardio and his friend Monson drove to Las Vegas and picked up jewelry and furs worth around half a million dollars from Sandy’s house.

“At this point in the investigation it became very clear that Sandra Bentley was not being forthright and honest with us,” says Tim Shaw, a retired detective with the Los Angeles Police Department. Still, Sandy continued to deny she knew anything about the jewelry or why Monson and Tardio were killed.

The LAPD executed a search warrant on Sandy’s L.A. home, and she quickly began cooperating with investigators. Police say Sandy admitted Tardio took the jewelry from her Vegas house in the wake of Yagalla’s legal troubles. Sandy said she phoned Tardio and told him she was about to lose everything, so he and Monson hatched a plan to steal the jewels and furs before Sandy was forced to hand them over to the feds, according to police.

Back in Los Angeles, Tardio was unable to sell the bounty. As time passed, he continued to look for potential buyers and became acquainted with Jacobs, who claimed to Tardio he had a buyer for the jewels. Tardio enlisted his friend Monson’s help and the two arranged to meet with the mystery man — who Jacobs later told police he knew only as “Mr. Big” — the night of the murders.

Jacobs never revealed the mystery buyer’s true identity, and it remains a mystery to this day. The jewelry has never been found.

Now, police are left with only theories about who killed Tardio and Monson. “The thing with Michael and Chris, they had no street smarts,” says Cox, the former LAPD detective, “and when you get yourself involved in that you’re going to get hurt.”

Sandy reportedly went on to start a family, and she and her sister have largely remained out of the spotlight. The investigation into Michael Tardio and Chris Monson’s cold case murder was recently reopened.

Anyone with information about the crimes is urged to contact Los Angeles County Crimestoppers at (800) 222-8477.

For more on this case, stream The Playboy Murders: “Double Trouble” on Max.