Rose was torn from her dream (a rather nice one about a tall, leather-clad bloke and a big, four-poster bed…) by a loud, jarring wailing. "Mmm… go'way…", she mumbled into her pillow as she turned over to escape the noise. It didn't stop. Mouthing an obscenity, she lifted her head and blinked away the fuzz so she could see her alarm clock.

02:34, GMT – great. She'd asked the Doctor why he set the TARDIS clocks to London time, and he'd responded it was easier on the humans he tended to travel with. She privately suspected it was because it would be hard to calculate Gallifreyan Standard Time given that the planet no longer existed, but wisely avoided the topic. Either way, she knew it was Too Damn Early to have been woken up. The noise was still going on, coming from the direction of the Rest Room. Grumbling something about shears that would have any right thinking man crossing his legs nervously, she threw back the covers, pulled on a nightie and went in search of the source of the sound…

As she pulled open the door of the Rest Room, Rose's bad mood evaporated instantly and she fought back a giggle as she took in the incongruous sight before her. Jack strumming away at an electric guitar was bad enough, but the spectacle of the Doctor playing the drums – rather well, she had to admit – was… well… she tried to think of a reason why, but the sight of three empty bottles of vodka answered her question for her. With the sonic screwdriver broken after that run-in with the Fevori, Jack had obviously been showing the Doctor how he coped on late nights when there were no shelves to put up… She lent against the wall, fighting back a yawn as she watched the pair of them finish up the tune – not one she recognized, but catchy – and tried to stop her mind descending to gutter level as she admired both Jack's nimble fingering and the Doctor's stick control.

"Hey, Rosie!", Jack beamed as his last power chord died away, "Sorry if we woke ya, but you're just in time – we could use a good vocalist!"

Rose grinned back, "Ta for the offer, but I was never any good at singing. What's the tune, anyway?"

"Moon over Orion", the Doctor piped up, "One of the best retro rock attempts of the 23rd Century…".

"Nice. Since when do you have an electric guitar onboard, though? Not to mention the drum kit…"

"Gift from a friend.", the Doctor replied.

Jack looked the guitar over, "Great friend, if he can get you an axe like this. Who was it?"

"Hendrix."

Jack looked stunned, "… Name-dropper!"

The Doctor gave him that grin.

"So who arranged the drum kit?", Rose enquired.

The Doctor had just started to reply when a loud, sonorous bell tolled a mournful note that echoed throughout the TARDIS.

"Oh, great… don't tell me the TARDIS is joining in with the jam session!", Rose joked.

But the Doctor wasn't laughing. His face had gone grave, then he bolted for the door and ran for the Console Room. Rose looked at Jack, who was as shocked as she was, then by unspoken consensus the pair of them legged it after the Doctor…

He was dancing around the console, frantically punching controls with a look on his face that reminded Rose of when they'd faced the Dalek. "Doctor, what is it? What's wrong?", she asked nervously.

He kept working as he looked up grimly at her, "That sound was the Cloister Bell. It only chimes when there's imminent danger to the TARDIS itself or to the entire fabric of Time and Space. Last time it sounded was the end of the Time War – took it a week to stop…".

Jack felt himself sober up rapidly as he asked, "So, what's the problem? Is the TARDIS in danger of being destroyed?".

"No,", the Doctor grinned, "your guitar playing isn't that bad… but from these readings something is messing with the fabric of Time on a massive scale…".

"The Time Agency?", Jack asked, his face pale.

The Doctor smirked, "That lot? Nah. No offence Jack, but your old employers are small potatoes compared to whatever's causing this disturbance.".

Rose broke in, "So who is it?".

The Doctor's face resumed his worried look, "I don't know. Only one way to find out…".

With that, he threw a lever and the whole TARDIS lurched as the ship performed a U-turn and span off through the Vortex in the direction commonly known as Trouble.

CUE TITLE CREDITS…