When we first meet Dory, she's just swimming around minding her own business when suddenly she bumps into Marlin and instantly offers to help him hunt down his son. This tang fish is actually a great partner to have by your side… if she can remember who you are for more than five seconds.
Let's take a closer look at this little blue dynamo.
Out to Sea
Okay, so we find out pretty quick that Dory's got some issues. The biggest one is that she suffers from short-term memory loss. Hey, at least she can remember her condition.
But she can't remember much else:
DORY: Hey, I've seen a boat. It went by not too long ago. It went... this way! It went this way!
MARLIN: Wait a minute! You already told me which way the boat went.
DORY: I did? Oh dear...[…]I'm so sorry. See, I suffer from short-term memory loss. […] I forget things almost instantly. It runs in my family… or at least I think it does. Hmmm… where are they? Can I help you?
All in all, trying to get help from a forgetful fish is pretty frustrating. Dory seems totally oblivious to the dangers around her—she willingly heads off to a shark party, complains there's not enough light while being attacked by an anglerfish, and hops on the tops of jellyfish during a race. Dory might be fearless, but she only because she doesn't remember to be afraid.
Dory's ditzy ways easily make Marlin lose his patience. She's one of those fish that causes delays and he just doesn't have time to lollygag through the ocean. He's looking for his son, dangnabbit.
And Marlin's not the only fish in the sea that Dory's rubbed the wrong way. Her family's is gone. She doesn't have any friends or companions to hang out with. Even if she did, she probably wouldn't remember them. Nope. Hanging out with Dory is not the easiest thing in the sea.
Little Fish, Big Helper
So, why does Marlin stick with Dory all the way to Sydney? Maybe it's because she's actually not as bad as she seems at first glance. Dory might be forgetful, but she's also unfailingly kind and generous. Think about it—she offers to help Marlin find his son without a second thought.
She puts herself in harm's way to hunt down a little fish whose name she can't even remember. Is it Nemo? Or Elmo? Or Harpo?
This little blue fish is also pretty darn smart. She reads human. And speaks whale. Where did she learn to do all this stuff? The world maybe never know. Her optimism and just-keep-swimming attitude is a nice balance to Marlin's totally pessimistic outlook on ocean life. Dory's ability to see the good and the positive is what helps her and Marlin escape many, many fishy situations.
And really, in the end, Dory is just right about so many things:
MARLIN: No. I promised [Nemo] I'd never let anything happen to him.
DORY: Huh. That's a funny thing to promise.
DORY: Well, you can't never let anything happen to him. Then nothing would ever happen to him. Not much fun for little Harpo.
She might not be the brightest fish in the sea, but Dory manages to hit the nail on the head without really knowing it sometimes. It's because of Dory that Marlin finally learns to let go and allow Nemo the freedom he needs to grow and experience life. Dory teaches Marlin to see the bright side of the sea. He doesn't need to be so terrified all the time.
Maybe things will turn out okay just this once? Maybe they won't be swallowed by a whale after all?
Fishy Friends Forever
Okay, so maybe the question we should be asking is why Dory sticks with Marlin. After all, he's not very nice to her and he keeps getting her into all kinds of scary situations. Why not swim off and find some other fish to bother?
But, it's clear that Dory gets something from Marlin, too. Mainly help for her memory and friendship issues:
DORY: No. No, you can't. Stop! Please don't go away. Please? No one's ever stuck with me for so long before. And if you leave... if you leave... I just… I remember things better with you. I do, look. P. Sherman, forty-two... forty-two... I remember it, I do. It's there. I know it is, because when I look at you, I can feel it. And I look at you, and I... and I'm home. Please... I don't want that to go away. I don't want to forget.
Dory knows that it's not easy to be with her and she appreciates Marlin's friendship. His constant presence in her life also helps with her memory loss. When she sees him, she remembers things. She knows that, with him, she has a friend who cares about her and wants what's best for her.
That's something we don't ever want her to forget.
The Voice of Dory
Dory is voiced by Ellen DeGeneres, even though Andrew Stanton originally envisioned the character as male. He said that one day he was watching The Ellen DeGeneres Show with his wife and he watched the energetic host change subjects at least five times before finishing a sentence and he knew she would bring the perfect spirit to Dory.
Lucky for us, Ellen thought so too.