Headscratchers / The Host (2006)

• How in the world did Hyun-seo survive her plunge underwater?
• What were those rashes all over Gang-du's back when he was in quarantine? Either, as Hee-bong says, it could be because Gang-du doesn't bathe. It could be the polluted water of the Han river. Or it could be that Gang-du has a food allergy which makes him break out all over, either to bread or seafood (he's shown scratching his back when he's shown eating a tinned mollusc at night)
• Why didn't the Agent Yellow affect Gang-du?
  • My best guess is sheer willpower (possibly Achievements in Ignorance). Either that or the brain probe which might have given him extra strength. Or he's a demigod like Wonder Woman.
• How did Se-joo survive the monster for the second time and not Hyun-seo?
• How does Hee-bong know the young men who drove him and his family out of the hospital?
• If the bottles of chemicals were dusty, why did they dump out all the chemicals inside instead of just wiping them off?