Well, it's hard to say for sure. Sometimes authors draw inspiration from various sources, but it doesn't mean it's strictly based on a true story. It could be a blend of real and fictional elements.
Definitely not. 'Girl in the Basement' is a made-up tale. The creators came up with the storyline and elements to tell an exciting and dramatic story, not drawing from real-life incidents.
It's not a true story. The movie is more of a fictional tale that takes inspiration from various sources but doesn't have a real-life basis. The plot and characters are developed for the sake of entertainment and to engage the audience's imagination.