While testing the Fantasti-Car, it begins to fall out of the sky and Reed passes out. Saving themselves, the FF bring the unconscious Reed to a hospital. There he is diagnosed with fatigue brought on by overworking himself.

Sue is captured by the Monster from the Lost Lagoon, who manages to escape the hospital with her as it's prisoner. Johnny tries to save her but the creature manages to escape. Not remembering who Sue's kidnapper was of who captured Sue, Ben and Johnny return to the Baxter building to consult it's computers and it concludes that it was probably the Monster from the Lost Lagoon.
While at the hospital, Reed revives and is told of Sue's kidnapping by a monster, but when he tries to leave to rescue her, he passes out once more. Sue awakes to find herself trapped in a cavern, Sue turns invisible to make the monster believe that she escape. Left alone, she unties herself and tries to pry open a crack in the cavern to escape. However, instead of escape, she brings a torrent of water splashing in that threatens to drown her.

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