The Gigantic Octopus was once on display at the Smithsonian Institution, but was stacked away into the Federal Archives. He is the former secondary antagonist of Night at the Museum: Battle of the Smithsonian. When he is not under Kahmunrah's control, he is kind, selfless, energetic and nice. Under Kahmunrah's control, he is cruel, ruthless, dangerous, aggressive and persistent. His defeat is gets defeated by Mr. Custer who saves Larry and dies.
Night at the Museum: Battle of the Smithsonian
The octopus appears in Night at the Museum: Battle of the Smithsonian. Kahmunrah hipnotized the Gigantic Octopus the night the Tablet of Ahkmenrah is stolen. While exploring the archives, Larry found a huge crate and after opening it, the inanimate octopus spilled out. Since the octopus wasn't alive yet, Larry put it back in and closed the crate again. After being captured by Kahmunrah, he tells him that he thought that he might have wanted the "Cube of Rubik". Larry takes Kamunrah over to the crate which the gigantic octopus has been stored in and opens it again. The octopus bursts out and knocks everyone off there feet (grabbing several Egyptian soldiers and flinging them at several other crates, releasing a smilodon skeleton and a pteranodon to attack the other soldiers in the process), giving Larry enough time to grab the Tablet of Ahkmenrah and escape. While he was escaping, however, he ran into the octopus, who used one of its tentacles to shove him at on other crate, releasing a hippopotamus. It also released some penguins and a giraffe from their containers. Before it got to Larry, however, George Armstrong Custer drove over in a motorcycle, which Larry gets into.
Later in the movie, the gigantic octopus reencounters Larry and Amelia Earhart, who were trying to decode the tablet, in the National Gallery of Art, but it doesn't attack. The pair sees that the enormous cephalopod is dehydrated, so Larry soaks it with water from a painting, rehydrating the octopus and befriending it. The octopus even gave Larry a hug after Kahmunrah is defeated.
The octopus also joins the battle with the other exhibits against Kamunrah, grabbing soldiers and gangsters with its tentacles. Near the turning point however, it became exhausted from dehydration again, in addition to its tentacles being overpowered, but it eventually regained its strength and continued fighting.
At the end off the movie, the gigantic octopus is released into the Lincoln Memorial Reflecting Pool as Larry instructs it to be back in the Smithsonian by sunrise. It waved its tentacles at him and his friends as they left Washington D.C.
- Amelia defines the octopus' gender as a male.