The song lyrics here come from Holding You by Dolly Parton. Enjoy x

"You've chosen the wrong person to possess, Mandragora," the Doctor said, fighting to keep his voice even. "Sarah's strong. She'll fight you."

"Oh, I don't think so, Doctor," the Helix hissed in Sarah's voice. "She's weakening already. This body is only temporary. You are my ultimate target."

"So why not just take me?" he protested. "Why make Sarah suffer?"

"I need to weaken you first," the Helix replied. "And this is how I shall do it. By destroying the one you love most. She's rather fond of you as well, you know. Oh, the memories she has. So vivid, so easy to manipulate."

"Leave my mum alone!" Luke cried. "What can we do, Doctor? There must be something."

"There's nothing you can do," Mandragora sneered. "Sarah Jane Smith is mine!"

But the Doctor was smiling. "There is something we can do. And thank you, Mandragora, for the idea. Memories! Sarah needs to remember who she is to drive out the Helix."

"Okay. Remember us, Sarah Jane," Rani called out. "Remember all the things we've seen. Like the Sontarans, the Judoon, the Mona Lisa."

"The Trickster," Clyde cut in. "And Maria. Remember her."

"Aaaah!" Mandragora screamed. "Too much! It hurts!"

"Remember me, Mum," Luke joined in. "Remember the Bane and Mrs Wormwood."

Mandragora screamed again and Sarah Jane's body collapsed against the Doctor.

"Remember me, Sarah," he said softly. "All the things we saw and did. Davros, Eldrad, the Zygons. Remember how much I love you."

One final shudder coursed through Sarah's body. A bright flash of purple energy left her she was suddenly limp in the Doctor's arms. He lifted her carefully and made his way toward the exit.

Several hours (and many Jelly Babies) later, Sarah Jane was back to her normal self, if a bit drained. Now, she and the Doctor were relaxing on the sofa in the attic. Luke, who seemed remarkably accepting of the new situation, sat in a chair nearby.

"Doctor," Luke said, "is it possible that the Helix could come back?"

"Well, potentially," the Doctor replied. "But not for a long time. It will need to rebuild itself and wait for the correct celestial alignment. It was broken when it left Sarah. Who knows, it may disintegrate before it reaches its destination." He planted a soft kiss on the top of Sarah's head and she snuggled closer to him. "Anyway," he continued, "I'm sure you don't want to talk about that all night. Tell me about some of the things you've done."

Luke happily chattered away about their adventures, wisely leaving their battles with the Trickster until the end. Sarah could feel the Doctor's arms tighten around her as Luke described how she had been deceived by the Trickster. She knew that she was lucky to be so well loved.

Once Luke had finished his tales he left to go to bed, leaving Sarah and the Doctor on their own.

She stood up and offered him her hand. "Do you want to dance?" He nodded. "Choose us some music, Mr Smith."

The music began and swayed together. Gazing into each other's eyes, both became lost.

My heart beats wild and deep.
Every thought in my mind has your name on it.
Hard to breathe, I can't speak,
Think of your love and just how much I want it.

Sarah focussed only on the gentle touch of the Doctor's hand on the small of her back. She melted into his touch.

And when I'm touching you, I feel a sudden change.
When I'm kissin' you, I taste the sun and rain.
When I look at you, I hear the angels sing.
And when I'm holdin' you, I'm holdin' everything.

She was intoxicating to him. He could easily have stayed with her forever.

And when you're touchin' me, I feel a sudden change.
When you're kissin' me, I taste the sun and rain.
When I look at you, I hear the angels sing.
You're everything, I'm holdin' everything.

A spin out – and back in. "Kiss me," she breathed.

Everything, you're everything;
Everything, you're everything to me.

In the morning, Sarah woke to find the Doctor's arm wrapped protectively round her waist. She sighed contentedly and relaxed against him, not wanting to fully enter reality yet.

"Morning," he murmured.

"How long have you been watching me for?" she chuckled.

"Not sure. I've lost track."

She could happily have stayed lying in his arms for eternity, but she could hear the sounds of movement issuing from below. She would have to get up. She reluctantly extricated herself from the Doctor's embrace and slipped her dressing gown on. She looked back at him and smiled.

"Come on, you. Up."

It was many hours later before the Doctor could bring himself to leave. After he had said goodbye to Luke, Sarah walked out to the TARDIS with him.

"Goodbye, Doctor," she said, tears filling her eyes.

He cupped her cheek and gently wiped away her tears. "Goodbye, Sarah," he replied. Reaching into a pocket, he took out a small red box. "I want you to have this. Don't open it until I'm gone."

He handed the box to her then pulled her into a tight embrace. They held each other for several minutes before the Doctor pulled away. Without saying another word he turned and entered the TARDIS.

Once the machine had wheezed out of existence, Sarah opened the box. Inside there lay a silver, heart shaped pendant bearing the inscription 'You have my hearts'. She smiled tearfully then turned for home.