It might just be that Love Island life wasn't for him and so he made a decision to leave, we'll just have to wait and see what other drama unfolds.
Hardcore fans have been sharing their thoughts on Twitter and while it's probably just the usual speculation that occurs when a contestant exits a reality show without warning, fans are intrigued nonetheless.
ITV statement Why has Niall left Love Island?
It's not yet clear how Niall's departure will affect Georgia's status in the villa.
Alex said on Love Island: "For personal reasons unfortunately he can't continue or come back to the villa".
Georgia was understandably upset her partner had to leave Love Island. 'We got on really, really well.
The reason given by the show was that Niall had left for personal reasons, but since leaving the villa his friends say that the "can't get hold of him" and fans of the show have been questioning why Niall left? 'He's such a great guy.
She said on Tuesday night's episode: "Obviously I was coupled up with him so obviously I came closer to him than most people in here but it wasn't just that. And I look forward to catching up with him and having some fun with him outside". "He was actually my friend, my buddy".
Niall had got off to a good start on the dating show, first finding the tone with Kendall before she was "stolen" by Adam.
Love Island airs on ITV2 at 9pm on weekdays and Sundays.