Johnny Sokko and His Flying Robot

Destroy the Dam (1x17)

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A huge, strange plant which suddenly appeared in Sagami Lake, sucks in all the water including a sailboat and its skipper. Attacking the monster plant with bombs only feeds it and soon it is setting the land ablaze with flaming projectiles of its' own! Only a plan devised by Johnny Sokko and enacted by Giant Robot can vanquish the vine!