It's been years that Alice has been back to Wonderland. Hatter has been waiting for his Alice to come back but she hasn't. He's worried that she is in trouble.
He asks the white queen if he could go to her world for a few days just to check on her. When he gets there, he notices she's much older. He doesn't mind because he still knows she's HIS Alice.
When they catch up, Hatter starts to love her. He doesn't know what love is though. Does he tell her? Or live a life wondering if she loves him back and never get to see her again?
He returns to Wonderland asking if he could stay in Alice's world and marry her. But, he only has 3 days to marry her.