Finding Dory, out in US theatres on Friday, picks up a year after the events of 2003's Finding Nemo, and sees Dory, a chatty blue tang fish with short-term memory loss, living in the peaceful ocean habitat alongside Nemo the clownfish and his father Marlin.
“She was apologising still for her shortcoming that she thought she had for her short-term memory loss and she could easily forget Marlin and Nemo and not find them again. I felt that she was completely unresolved,” Stanton said at a press briefing on the film.
Finding Nemo grossed more than $900 million worldwide and won an Oscar for best animated feature.
Pixar's Finding Dory is expected to open with around $115 million at the North American box office this weekend according to Variety, and is a strong awards contender for its owner, Walt Disney Co.
Unlike the rescue mission in Finding Nemo, in which Nemo was captured and taken across the world as his father chased after him with the help of Dory, Finding Dory mostly takes place in the confines of a marine institute and introduces a host of new animal characters.