She'd forgotten what it was like, the first landing on a planet. The thrill of the unknown, fear even, tingling up and down her spine; the anticipation.
"So, Sarah. Shall we?" Her Doctor - she had always thought of him as that - held out his arm expectantly.
She hesitated, looking from him to the closed doors and back again. "Where are we?"
"Oh...I don't know! Only way to find out is to find out, eh?" He reached over to the console and flicked the door switch, and Sarah Jane suddenly felt as if the years separating her from the last time she'd walked out of those doors had vanished, evaporated in the heat of his infectious enthusiasm. She stepped confidently towards the exit, curious and ready - well, almost ready - to see where she'd been brought this time.
He watches her. She's grown up, his little Sarah Jane, grown up so much since he saw her last that he wonders if he did the right thing by leaving her. There's sadness in her eyes, sadness and a tired fear that he knows well. He's always known she was strong, but this...this is different. And he feels somehow responsible for it, and therefore somehow responsible for bringing the smile back in to her eyes.
She steps towards the doors, curiosity winning over her obvious apprehension, and she looks so much the same that he almost forgets that over 30 years have passed for her. Did she think he'd abandoned her? Surely she knew he would never do that - not to her.
She walks outside.
For a minute, she was so glad that they hadn't landed in another blinking quarry that her surroundings didn't quite register.
It was a world away from Bannerman Road, and she nearly laughed at the sheer impossibility of what she was seeing.
The sky was dark blue, edged with purple in places. No visible light source, thought her journalist's brain: that's weird. They'd landed on top of a cliff, the dizzyingly sheer drop about six feet in front of her ending in transparent water that extended all the way to the horizon.
But stranger than that - curioser and curiouser, she thought absently - was the door.
"Sarah," came the Doctor's amused voice from behind her, "why is there a door hanging in mid-air?"
As if she knew. Gingerly, she crept closer to the edge of the cliff and peered at the door. It was wooden, polished and lacquered and boasting an impressive knocker in the shape of a dragon's head which looked like it was made of bronze.
"Doctor...this can't be possible. The laws of physics...surely..."
"Oh, come on!" He seemed to thrive off impossibility, her Doctor. It was his fuel. "All good laws have exceptions!"
"Okay...so there's a door in the sky."
"Indeed. And what are doors for, Sarah Jane Smith?" he asked gleefully. He'd found himself another puzzle, she realised, and he intended to solve it.
She stepped back, away from the cliff edge, and backed towards the TARDIS. "Oh no, Doctor. No you don't. Not again, not this time." She was panicking, she knew, over-reacting completely. Hell, she trusted him with her life. With more than her life - with her heart and soul - but this, right now, she couldn't do.
She's scared.
Sarah Jane Smith is scared.
He's uncertain now, wonders what has happened since he left her, but her fear is real and he can see her shaking as she leans against the TARDIS. Seeing Sarah like this worries him: she was always so strong, before.
"Sarah?" he says, stepping towards her. "Sarah, it's me, it's safe."
He doesn't know what to say, not really. This regeneration has never really been able to talk about feelings and suchlike very well. So he's surprised when she moves tentatively towards him and puts her arms around him; he can hear her crying softly against his shoulder.
"I still can't believe it's you," she says, her voice muffled against his coat. "I missed you, and I waited for you for so long...and now I'm acting like a child."
"Oh, Sarah, I would never think that. Now, tell me all about it."
He thinks she's about to say something important but suddenly her breath draws in sharply and she stiffens against him. "Doctor," she whispers, "the door..."
He glances around to check but finds that he has no words of reassurance.
The door is opening, and through the slowly widening crack he can see something that is definitely not blue sky.
"Open sesame," he mutters to himself.