The moment Hatter sees Alice go through the mirror, his heart stops beating.
Before anyone can stop him, he crosses the room and throws himself through the mirror. It's madness, but then again he's never been that much sane to begin with and he isn't about to start now. He opens his eyes to a pale and shivering Alice, sweating on the floor.
He holds her to his chest and screams for help and when the ambulance gets there, nobody can make him let her go until after they reach the hospital.
One day later, Alice wakes up.
Hatter knocks on the door and greets her mother - marvels for a second on how mother and daughter can be so different from each other and still managed to give off the same air of confidence and mystery. He doesn't wonder for long, though, because then Alice comes in and screams his name and his heart painfully pounds inside his chest once again.
They kiss and Hatter can almost cry at the way she holds on and relaxes against him with complete trust. Their kisses are open mouthed, gentle and slow - a deep contrast to the fast-pace they've had since the beginning of their acquaintance - not caring about her mother watching them in shock.
"I missed you." It's not exactly what he meant to say, but it's true nonetheless. She was gone for a night, but it seemed like so much more.
Alice sighs against his mouth and it might be wishful thinking, but Hatter thought it sounded a bit like "I love you too."