For “Marriage Boot Camp: Reality Stars” participants Mike “The Situation” Sorrentino and his longtime girlfriend, Lauren Pesce, the lie detector test determined that was a lie. Everyone on the cast was given a lie detector test before the final episode, but the results revealed something shocking for Mike and Lauren, a sneak peek clip for the WEtv reality show exposed Friday.

On the test, Mike was asked if he trusted his girlfriend “100 percent.” He said, “yes,” but the test indicated he was deceptive. When Lauren was asked if she engaged in physical, sexual contact with anyone other than the MTV “Jersey Shore” alum, she said “no,” but the test determined that was a deceptive answer.

“I felt like I was getting punched in the face,” Lauren said about the results. “I’ve been 100 percent truthful and honest about everything.”

But Mike didn’t believe her. “Well if mine said I had problems with trust and hers said that she was deceptive then I guess it’s valid,” he said.

The infidelity reveal is a shock for Mike and Lauren, who joined the show because of Mike’s addiction and legal woes. Most of the focus has been on the “Jersey Shore” star and his attention seeking ways, so cheating on Lauren’s part is not what most fans expected.

However, Mike and Lauren aren't the only couple that has an explosive lie detector test reveal. In the episode titled, “Web of Lies,” one of the couples leaves the show early. “The truth could set you free….from your relationship. With only 24 hours left until the final ceremony, the reality stars are blindsided when they find out they will be wired up…to take a lie detector test!” the description of the show said, according to Hollywood Life. “Each person will get to ask their partner one burning question they need truthfully answered before they make their final decision to stay together or call it quits.”

To find out which reality stars told the truth or lied, don’t miss an all-new episode of “Marriage Boot Camp: Reality Stars” on WEtv Friday, at  9 p.m. EDT.

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