1. I sort of get what you meant by this, but the hallucinogen affected people's minds by projecting what they expect to see out in the real world. Once they realized that Folsense was actually a decrepid town, that's what it then looked like to them. They didn't actually escape from the drug, they just realized what Folsense truly was so the drug became irrelevant at that point (actually, you know what's sad? Everyone you met in Folsense is actually 50 years older than what they appeared to be
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).
2. No, this had something also to do with the hallucinogen. Every person who opened the box before Professor Layton's professor expected to die once they did, and then it actually happened. Professor Layton's professor opened the box with a skeptic mind, so while he was put into a comatose state he didn't die from it.
3. I don't see what's wrong with Beluga. He realized that there was no treasure to be found in Folsense and came to terms with his selfishness (if I remember correctly). He also got reunited with his long-lost brother. Chelmey doesn't get any closure because he's a recurring character. Play the third game if you want real closure on all the main characters.
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