You never watch Hey Arnold? Here's the background:
The very last episode was a movie length special of the origin of Arnold's parents and how they got together and gave birth to Arnold. There were hints that could unfold in the later episodes, like the mysterious tribesmen. So the end of that special have Arnold discovered a map that leads to his parents' whereabouts. And it ended and never concluded.
We don't know what happens next. We don't know what secrets unfolds. We don't know if Helga and Arnold get together. We got nothing. The creator said that it was supposed to be a movie to continue the story of his parents and pretty much conclude it there. There's even a lost footage surface on the web.
But now, *plays a holy light soundtrack like, with sun shines* we are finally going to get our long waited conclusion.
Actually, the fans have known forever what happens-that's why there's been a years long drive to get it made Craig Bartlett has talked about it in multiple interviews. Arnold admits to loving Helga, they kiss, but it's interupted by Gerald in a comedic way. Arnold finds his parents, who have been chasing after the villain who wants the Green Eye's treasure. The villain kidnaps Arnold's classmates and holds them threatens Arnold to tell him where the Green Eyes are, etcetc. Arnold and Helga do end up together, they get married, have children, all that jazz.
Skip to 7:42.
That being said, this movie is not for the old fans of the show. Nick stated it's only for their 6-11 demographic and Bartlett said he has to find a way to make it accessible to them. They're also getting a redesign.