The Giant Squid is the secondary antagonist in Finding Dory.
The giant squid is first seen sleeping at a nearby sunken shipping container at the Midnight Zone. After Dory talks very loudly, as the hermit crabs try to shush her, Marlin, and Nemo, the giant squid awakens and emerges from the container. It then swims after the trio, until eventually being trapped in another shipping container. Unfortunately, the giant squid grabs Nemo with one of its tentacles and attempts to eat him as Marlin and Dory try to stop it. Fortunately, a nearby rock crushes the container the giant squid is in, killing it in the process.
Strangely enough, the giant squid is shown to be alive in the end credits, as Hank is seen swimming away from it. It is unknown if it is the same giant squid, or another one resembling it.