Viewers were left gobsmacked last week when Sam visited Ines' apartment for a secret rendezvous.
While their affair is seriously heating up on-screen in Married At First Sight, Sam now admits he wishes he'd never met up with the legal assistant in the first place.
"If I had my time again, I probably would never have opened her message," Sam, 26, tells TV WEEK.
"But it was in the moment and I was paired up with someone I didn't get on with [Elizabeth]. The whole point of applying was to meet someone I could fall in love with. Ines seemed more my type and I was intrigued as to who she was as a person."
However, Sam says he's since changed his mind about the striking brunette now he's had the chance to see how poorly Ines has treated her on-screen husband Bronson.
"It's terrible and embarrassing," he says. "The way she treated him is a true representation of herself. Obviously, I was blind to that – all I saw were the smiles.
"She seemed lovely, but you never know what you're going to get with her. She's manipulative and smart."
At last week's Commitment Ceremony, Ines, 28, decided to stay with Bronson after telling the relationship experts things were improving between the pair, who are obviously ill-suited. But her real intentions are clear.
"I just want Sam," she says on camera. "I don't want to work on my marriage now. Every time I look at him, I just want to have sex with him."
Meanwhile, Sam also has a motive when he agrees to continue with the experiment: he says he wants to find out "what's going on" with Elizabeth.
But he later admits on camera he's "done and dusted" with his wife and is staying only to see if things with Ines progress.
"She's keen and wants to take this a step further, and that's amazing," he says.
But Sam and Ines' clandestine affair doesn't remain so for long. This week, their MAFS co-stars get wind of the romance – and aren't happy.
"Ines suddenly had a lot to say about Sam, so I asked her if she fancied him," Jules, 36, explains. "She said no. Little did we know they'd been seeing each other.
"We didn't know what was going on at all. That was an opportunity for her to be honest. She lied to everyone."
Cyrell, in particular, doesn't hold back her opinion about the affair, as she has been cheated on in the past.
"I was like, 'How can you do that to good people?' They could have just been honest," Cyrell, 29, says.
"The sneaking-around part got to me the most. It's how they went about it. I don't like fake people and I don't like liars."
Married At First Sight airs Monday to Wednesday, 7:30pm, and Sunday, 7pm, on Nine.
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