The Doctor ran along the seemingly endless gleaming white corridors, slamming door after door in his wake. He paused, panting for breath, and mopped his brow with the frilly cuff of his sleeve, green velvet jacket crumpled and sticky from his exertions. He hadn't run like this for ages, and could feel a dull throb of pain coming from his leg where he'd been wounded in the Crimea.

He leaned against the concrete wall and thumped the side of the steel door that blocked the corridor he was currently in.

"Solid titanium! Built to last!" he wheezed, grinning in triumph.

A faint, acrid smell tickled his nose. His breath caught in his chest. Before his terrified gaze, a dull red spot appeared in the centre of the door and spread rapidly.

"No! NOOOO!!" he cried, backing away before clumsily turning and resuming his flight down the corridor.

Behind him, the steel door began to sag and melt...

***

He charged into a room and slammed the door behind him. Quickly he began to pile furniture against the door.

"Will this never stop?" he gasped frantically, jamming a filing cabinet across a trestle table. He looked around for more furniture to block the entrance with, but there was none. He'd used it all. All that remained was a trill-phone, sitting on the floor in one corner. The Doctor dashed over and snatched it up. Cradling the receiver under his chin, he began to dial. After a couple of rings, someone picked up.

"Duty officer? Get me Lethbridge-Stewart, man - quick!" His hands shook with impatience and he eyed the barricade dubiously. If solid titanium couldn't hold...

A familiar voice came over the line. "Alistair!" the Doctor squawked. "For God's sake man, do something! I'm cornered! Send help immediately!" The voice rattled off something. "I don't care why you've sent number one platoon to Egypt! Send somebody! Anybody! Sergeant Benton, Sergeant Osgood, Corporal Bell, even! Anybody!"

Suddenly the line went dead, and the lights flickered and died. Fear gripped the Doctor's hearts. He heard footsteps grating on the uneven floor outside the door. Then, with a terrifying groan and screech, the door began to be forced inwards. Furniture spilled from the pile and clattered noisily to the floor. The Doctor shrank into his corner in sheer terror, as the door was finally forced open. A huge, misshapen silhouette filed the doorway. The Doctor flung his arms over his head and screamed...

"Oh really! What a welcome!" snapped a high-pitched feminine voice. "Anybody would think I was going to murder you or something, instead of bringing you a nice Valentines gift!"

The figure stepped into the room as the lights came back on. It was a tall, striking young lady with a flowing mane of long blonde hair wearing the shortest pink microdress known to the universe. She tapped one toe of her thigh-high yellow go-go boots impatiently and folded her arms, resting a large heart-shaped box of chocolates in the crook of her arm.

"Iris, please!" implored the Doctor. "How many times must we go through this charade? As if my exile weren't bad enough..." he moaned.

"You big baby!" she pouted. Then a big grin spread slowly across her face, and she tossed the chocolates aside to open her arms out. "C'mere and give us a Valentines kiss! Ah, go on, go on go on go on..."

The Doctor tried to shrink even further back into the wall as she advanced upon him.

"NO! Keep back! Keep back, I warn you... I know Venusian Akido! I'll do something with my sonic screwdriver! And not on THAT setting either! No! Keep back! Unhand me, madam! No! NOOOOOOOO....."