Karissa Shannon's break-up with
Sam Jones III wasn't based on a ruse after all -- because Karissa and her twin sister Kristina tell TMZ, they ARE moving back into the Playboy Mansion.

We broke the story this morning -- Karissa
pulled a bait-and-switch on the "
Smallville" actor yesterday, lying about moving back into the Mansion with her sister ... so Jones would help her pack before she dumped him.
But something changed in the last few hours -- because the twins just rolled up to the Mansion, telling us, they're moving back into
Hugh Hefner's palace after all.
The girls shacked up with Hef for the first time back in 2008 -- living with him as his "girlfriends" for over a year.
Their chart-topper hasn't even been released yet -- but TMZ has learned Playmate
Karissa Shannon and "
Smallville" star
Sam Jones have just called it quits.

According to sources connected with the ex-couple, Karissa pulled a cruel bait-and-switch before she dumped the actor.
First, she told Jones she needed to move back into the Playboy mansion for professional reasons ... but after he helped her pack up her stuff ... she dropped the hammer, confessing she was actually moving in with her twin sister ... and their relationship was over.
Sigh. And we were JUST starting to get that damn song out of our heads.
He's been a TV star ... a porn star ... and a convict ... but now
Sam Jones is trying his hand in the music industry -- teaming up with his
Playboy Playmate GF for the next summer anthem -- "Juice and Vodka."

Sam and
Karissa Shannon are both featured on the song -- which includes the hook, "Mix that Juice and vodka ... juice, juice and vodka. Mix that juice and vodka ... juice, juice and vodka."
The twosome is putting the song on iTunes next week.
He's out on bail facing 20 years in prison -- but ex-"
Smallville" actor
Sam Jones still needs to work ... which is why an LA court granted him permission to party in Mexico this week with his Playmate GF.

Sources close to the actor tell TMZ, Sam was paid to appear at Dady'O Nightclub in Cancun Thursday night -- alongside his GF
Karissa Shannon and her twin sis Kristina -- and in Hollywood ... that counts as a real job.
But Sam couldn't just hop a plane and fly south of the border ... the guy is awaiting sentencing for
his massive drug trafficking case -- scheduled for June -- and technically isn't allowed to leave the country.
So he did what any other actor in his position would do -- he filed papers with the federal court in L.A. asking for a special dispensation ... on the grounds that he needed the money ... and the court actually GRANTED it.
FYI -- the photo above is from the actual event. Celebrity justice at its finest.
Karissa Shannon's
sex tape partner wasn't 100% honest when he implied that he owned a certain badass
Rolls-Royce -- because TMZ has learned ... dude actually borrowed the car from a friend.
Sam Jones III stepped out of the baller Rolls Phantom outside
Premiere Supper Club in Hollywood over the weekend -- Karissa by his side -- claiming, "That is not a rental ... young mogul style."
Unfortunately for Sammy the real owner of the car -- Jay Grdina, the guy behind the website
kikster.com -- contacted TMZ and says, "Considering I have the only matte black Phantom in L.A. ... ole Sam just told a nice lie to TMZ."
Grdina tells us, Sam borrowed the car Saturday night as a favor ... free of charge. Mr. Young Mogul must have forgotten that part.
We took your questions on everything -- including
Lindsay Lohan's probation revoked,
Paris Hilton pleading guilty in her cocaine case, and our exclusive stills from
Karissa Shannon's sex tape.

Plus:
Sarah Palin will be at "
Dancing with the Stars" tonight to support Bristol.
Former Playboy Playmate
Karissa Shannon must have been extremely filthy before she shot her sex tape ... because she spends a whole lotta time in the bathtub and the shower.

These are non-filthy screen grabs from the video.
As we first reported, Shannon and her BF -- "Blue Mountain State" star
Sam Jones -- claim they tried to block the release of the tape ... but ultimately agreed to a deal with Vivid Entertainment after the price was right.
TMZ has learned ... former Playboy Playmate
Karissa Shannon and her BF, "
Smallville" actor
Sam Jones, have finally agreed to release their sex tape ... and all it took was cold, hard cash -- that's what she said.

Sources close to the couple tell us they both agreed to a deal with
Vivid Entertainment when the offer hit the "six-figure range."
Steven Hirsch -- the president of Vivid -- tells us, "We are excited to finally distribute this amazing DVD. Not only is it extremely kinky for a celeb sex tape, Karissa is absolutely beautiful. And as for Sam, let's just say he's no 'Smallville.' This is sure to be one of our all-time best sellers."
Watch your backs, Paris and Kim K -- sounds like you've got a challenger for the title.
We took your questions today on everything -- including
Oksana Grigorieva prepping to sue
Mel Gibson,
Kid Rock testifying about his 2007 Waffle House brawl, and
Karissa Shannon visiting
Vivid to talk sex tape.

Plus:
Katherine Jackson's wrongful death lawsuit against AEG.
Karissa Shannon may have had a change of heart when it comes to fighting the release of her sex tape -- and it all comes down to her suspicious visit yesterday to
Vivid Entertainment's headquarters.

Karissa and actor
Sam Jones III -- her boyfriend/sex tape partner -- were spotted outside of Vivid's office in L.A. yesterday afternoon ... where Sam confirmed they just had a meeting with Vivid boss
Steve Hirsch.
As for what the meeting was about -- Sam told our cameraman they were "exploring all of our options" ... then quickly covered his bases by saying, "Especially our legal options."
We took your questions on everything -- including an
NBA player's connection to the
Floyd Mayweather Jr. domestic incident,
Playboy model
Karissa Shannon unleashing her lawyers on
Vivid to block the release of her sex tape, and
Oksana Grigorieva still lawyer shopping.

Plus:
Britney Spears' ex-friend
Sam Lutfi accused of psychotic stalking.