Donna is in the fruit department at Tesco, reaching for the bananas, when she remembers.
It's the strangest feeling, having her mind expand in every direction, filling with forgotten memories (some her own, most not) and new - old - knowledge. It makes her really quite miffed to realise that it's been months and the Doctor still hasn't been back to fix her brain. Does she have to do everything herself?
Sylvia is out with friends and Wilf is up the hill with his telescope, so she has the house to herself when she gets home. Just as well; time is of the essence and if she's going to figure out a way to perform brilliant DIY brain surgery with whatever's around the house, it's better if no one gets in the way.
Donna glances at the expensive stainless steel toaster Sylvia bought the week before, and a grin creeps slowly across her face. Oh yes. That would do just fine.
She picks up a fork and gets to work.
Jack is just as cute as she remembers, even when he's gob-smacked.
"Donna! How did you--"
"Fix my head?" Donna flips her hair back and smirks. "I'd tell you, but it's really way beyond your understanding."
Donna pretends not to hear that. He'll find out sooner or later and she's really planning on being gone by then. "Aren't you gonna ask why I'm here?" she says instead.
"Fine. I'll bite. Why are you here, Donna?"
"I'm going to grow a TARDIS," she says. "Brilliant, yeah? A TARDIS all my own."
Jack replies with stunned silence.
Torchwood has a lot of interesting gadgets that they probably don't know how to use properly anyway. She's practically doing them a favour taking some things off their hands. For their own safety, really.
Fortunately, Jack doesn't notice her suspiciously pouting handbag (sadly not bigger on the inside), or that she pushes Matron Cofelia's sleek sonic pen up her sleeve when he turns his back. That one practically belongs to her anyway.
"The Doctor left this here for safekeeping," Jack says, and looks hesitant as he holds up the coral. "Are you sure this is okay with him?"
Donna grins widely. "Oh yes."
Well, what he doesn't know and all that.
Turns out, growing a TARDIS is really quite boring. Even with her genius solution it's going to take years and the whole Time Lord consciousness is doing nothing for her patience.
It's really a matter of pride to do it all on her own - the Doctor hasn't even bothered to check up on her once and make sure her brain hasn't gone splat. But he does have the only functioning TARDIS around, and now that she's practically a Time Lady, she needs a TARDIS. All of time and space are calling out to her, spelling her name in the stars.
She's supposed to be out there. One way or the other.
"You what with a what what?" Martha's jaw has practically hit the floor.
"Fixed my brain," Donna repeats. "With a toaster and a satellite dish. Oh, and a fork. Didn't have a sonic screwdriver, did I. Had to use what I had handy. Can I come in?"
Martha steps back to allow her entrance.
"I'm growing my own TARDIS, but it's taking too long," Donna says while Martha pours them tea. "I need you to get Skinny Boy here. You've got his number, yeah?"
"Are you going to... nick his TARDIS?" Martha asks, eyes wide.
That is actually not a bad idea. Except for the bit where it will surely make him pout and look like a lost puppy. It always makes her all wibbly inside, not that she'd ever admit it.
"I'm just gonna borrow it for a quick spin to the future," Donna reassures her.
"He does still owe me a wedding present."
"Ooh, tell him slimy squid aliens are taking over the planet and we really, really need him to save us. He'll be here in a jiff."
The Doctor bursts out of the TARDIS into Martha's kitchen with his coat halfway on and screwdriver in hand. "Steer me towards the danger, Martha Jones!"
"Yeah," Martha says. "About that."
"Oi!" Donna shouts and walks up from behind the TARDIS. "Watch where you park, Time Boy!"
The look on his face is rather priceless.
"Close your mouth," she says.
"Donna...? But... how... but... slimy squids...?"
Donna gives him a pitying look.
Martha steps up and pats him on the head. "For a genius, he's really a bit daft."
"Toaster," Donna repeats slowly. "Satellite dish. Brain. Fixed."
They're alone in the TARDIS. For some reason that may or may not have had something to do with bleeping screwdrivers and threats of bodily harm, Martha seemed to think they needed to be somewhere where she was not.
"That makes absolutely no sense," the Doctor says and picks up a new instrument to scan her with.
Donna doesn't dignify that with a response. Time Lords, sheesh. So focused on what can't be done. Leave them alone to think and you end up with a memory wipe.
"For the last time. Stop. Scanning. Me!" she says and shoves him away. "Here's how it is. I'm growing my own TARDIS. I just need to use yours so I can drop a couple of years into the future and get it."
His mouth drops open. "You what?"
"You can come too, of course," she offers generously.
Donna crosses her arms. "I knew I shouldn't have let your drive."
"What's wrong with my driving?" the Doctor says defensively.
"This is the other side of the flipping universe! We were going to get my TARDIS!"
The Doctor purses his lips and looks very stubborn.
Donna sighs. "I suppose we might as well have a look around now that we're here. But I'm driving next time."
"I don't understand," Donna says and stares are the screen. "I set the coordinates myself, how could we end up on the lost bloody moon of Poosh?"
"Technically, it's the found bloody moon of Poosh now. Anyway," he says, giving Donna a weird sort of sideways glance, "maybe the TARDIS wants you to stay."
Donna glowers back at him. "Don't be an idiot."
Donna opens the TARDIS doors and looks out on another strange, new world. It is getting ridiculous. Not that running for their lives and saving random planets isn't fun, and it reminds her of old times... but it's not how she'd planned this.
Donna looks at the Doctor and narrows her eyes. "Are you getting us lost in new and exciting places over and over on purpose, just to distract me into forgetting about my own TARDIS?"
"No." The Doctor looks very innocent. "Of course not. Me? Oh no. I wouldn't do that. Definitely not. Wouldn't that be silly of me?" He lets out a weird, loud kind of laugh.
Donna rolls her eyes.
"Right then," she says and closes the doors. "Apparently you're useless without me. So I've decided to stay on for a bit. For the sake of the universe and everything."
"Really?" He's grinning like a mad man. "Oh, Donna Noble," he starts.
"If you're gonna be all soppy," she interrupts, "I'm going to have to punch you."