The episode opens with a Military airplane being attacked by a Giant Mutant Hummingbird. At H.E.A.T. headquarters, Randy Hernandez is helping Mendel Craven with his email, and sees a message that leads him to believe that Craven is dying. They then travel to San Francisco to speak with the military about the downed plane and head up with one of the pilots to find it for themselves, and are attacked by the Hummingbird. Godzilla arrives to save them, but loses track of the hummingbird and retreats. With some gathered samples from the attack, H.E.A.T. discovers that the Hummingbird can only be seen at at least 500 miles per hour, and traces of redwood tree bark. While searching the Pacific Northwest of the United States, they are attacked by an entire flock of the Hummingbirds. They capture a live specimen, and discover that the flowers that a regular hummingbird would feed on have been polluted to contain a certain toxin that is also found in the military's aircraft's engines. Meanwhile, Randy and Craven have developed a special visor to make the Hummingbirds visible to Godzilla. They are able to attach it just as a flock of Hummingbirds begin to head for the city. He is able to defeat them, and it is revealed that Craven's "virus" was not in him, but in a mummy that he was autopsying.