We already know that Chrysten's arrival on the beach brings with it a HUGE bombshell, as Gaz later confesses privately to the camera that he had cheated on Lillie with Chrysten during a trip to Australia when they were dating.
Awkwardly, Lillie is already in the villa and will have to meet Chrysten and as you can guess, the truth eventually all comes out.
Lillie is left heartbroken to hear that Gary had cheated on her during their relationship of nearly two years, and admits she had no idea he had been unfaithful.
She breaks down in tears at the news and brands Gaz a "horrible person" for lying about Chrysten to her.
Chrysten, however, doesn't seem too phased by the drama. In fact, in a new video shared by MTV she claims she "didn't feel bad" for bedding Gaz, as she hadn't known he was with Lillie at the time.
She explains: "I met Gaz when he was on tour in Australia and the night I met him, I didn't know he was with Lillie until afterwards. He told me when he was leaving. I didn't really feel bad about the situation because Lillie was on the other side of the world and it wasn't really my fault."
Sharing her first impressions of Gaz, Chrysten adds: "My first impression of Gaz was that I thought he was cute, but I usually go for muscly guys."
She also reveals that she had been planning on hooking up with Gaz again on the show.
Explaining her reasons for heading to Thailand, Chrysten says: "The reason I wanted to go on Ex On The Beach because I thought it would be fun to meet Gaz... and I'm single and wanted to meet some hot guys."
Following her addition to the villa, Gaz is a little distracted with Lillie, however, and is left trying to apologise for his actions.
Chrysten, meanwhile, sets her sights elsewhere and ends up in bed with Jordan Davies locking lips with him instead!
Ex On The Beach continues Tuesday 20 September at 10pm on MTV.
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