Arriving in New York where Professor Hawkins can study Godzilla, Godzilla's cage is accidentally dropped and Godzilla gets loose, ending up in New York's sewer system. With the amount of time that Pym's shrinking gas will last in question, it's a race against time as everyone tries to find Godzilla before he returns to his normal size and rampages through the city.
While in the sewers, Godzilla comes face to face with a New York City sewer rat and easily kills it. Emerging from the sewers, Godzilla stumbles upon Robert who had snuck out of the Helicarrier to find Godzilla to be sure nobody hurts the monster. As the boy is reunited with Godzilla, he suddenly grows in size to the height of a human adult.