Agatha Christie wrote a book. It was called "and then there were none". It was smart. It was clever. It was downright spectacular.
Doubt is none of those, though it IS a blatant ripoff of And Then There Were None.
Unfortunately, the only thing it took from that story is the twist ending. Doubt has no concept for mystery writing. The writer could have come up with more intelligent murder mystery nonsense while jerking off in a cave.
Things to consider.
Magic fucking bar code tattoos. Because why not. Do they add anything to the plot? Nope! Do they guarantee that the person who set this nonsense up will 100% be caught? Hell yes they do!
The building. If its a building, you can leave. Doesn't matter what or where, not to mention that installing things like super security doors in old buildings is suspicious and impossible.
The villain. In this story, bodies are moved, people are hung, and everyone is gathered in a mystery building for this. Every bit of this proves that the villain is strong. Far stronger than a normal human. You think hanging someone is easy?! But yeah, apparently its all good, a little girl can do that.
Vague hypnotism. Whoever came up with that needs to stop writing. They aren't good at it, in fact they're an embarrassment to the entire concept of a writer.
No matter what genre you like, this sucks, skip it.