Disclaimer: Not mine.

AN: I asked for someone to send me a River/13 prompt from a prompt list and an anon answered.

Here's: 42. "I'm only here to establish an alibi."

* The Suspicious Case of Tribbles *

"What do you think?" Ryan asks Yaz as she's placing another armful of every shiny, reflective object she could get her hands on in a circle around what looks like a jury rigged mess of Christmas lights.

"I don't know, you're the expert here." Yaz tells him and looks on as he's screwing in the last green light bulb into place. If they were in an apartment on Earth she'd say that what it looks like is an invitation for a blown out sparking plug. But where they are, is inside the control room of the TARDIS so it is probably fine.

"I'm a mechanic... -ish. I know how to fix cars not how to make tribble traps." Ryan says.

"It looks fine, Ryan." Yaz assures him. And it does. It looks exactly like the Doctor said it should before she and Graham went off to bring the alien balls of chaos back to the TARDIS to be trapped.

They aren't of course actually called tribbles. But the word the Doctor used for them involved a lot of X's and Y's so when Graham named them after the Star Trek creatures, Yaz and Ryan went with it. They do look like tribbles even if what they act like are ping pong balls from hell.

Apparently they're some kind of pets. Unfortunately they're not native to this particular planet so when they all first stepped out to see some kind of - apparently very cool - jewel festival, it was already utter chaos.

It's as Yaz is wondering for the dozenth time about how exactly a dizzying number of the things even got there then, that the doors to the TARDIS smash inwards and a woman strides in, looking like she owns the place.

"Don't mind me. Carry on!" The woman says, dropping a bag of something heavy that sounds like a bag of rocks to the floor and hurrying towards the TARDIS controls. "I'm only here to establish an alibi. A short hop over to the other side of the hemisphere and some 38 planetary hours in the past should do it. I'll send you lot right back to him none the wiser. It'll be our little secret."

"Alibi?" Yaz says, immediately focusing on what feels like the most relevant part.

They were trained for this in the academy, learning to note down all identifying features even before the mind has time to fully catch up with whatever unexpected thing has just occurred. So she doesn't let herself flounder and just observes everything.

Human or human-like; Caucasian; extremely curly, blonde or light brown hair; maybe 5.6 foot tall; anywhere from mid-forties to mid-fifties; attractive; Southern English accent.

'And trouble.' Yaz adds to herself when the woman starts working the TARDIS controls - very expertly, - before either Yaz or Ryan can do more than get up to their feet in surprise.

They exchange a concerned look and abandon their project.

"Wait, stop!" they both yell, only halfway to the intruder as she pulls the lever that always precedes the TARDIS taking off.

The lever jams halfway down and the control room whines with an almost stubborn sort of noise. Yaz and Ryan share a relieved breath.

"Oh thank god." Ryan says.

"Well, that's strange. Did the old man forget to oil your controls?" The woman says and tries the lever again. This time the answering noise is much louder and gets followed by a shudder that knocks them all off their feet.

"Whatever has gotten into you, my dear?" The mysterious woman asks to the air above her the same way the Doctor sometimes does when she's talking to the TARDIS.

As if summoned by Yaz's thought the doors to the ship slam open again, this time letting in the Doctor and Graham.

And a great number of tribbles. They're acting much calmer than they did last time Yaz saw them, only jumping up to around the height of the Doctor's knees. She can actually kinda see now how someone could look at them as cute pets.

Graham stops in his tracks when he sees their unexpected guest but the Doctor is walking in backwards and waving around her sonic screwdriver, which is presumably why the little critters are very calmly acting out a scene from Pied Piper.

"Doctor?" Ryan says uncertainly from beside her. "I think someone just came in to steal the TARDIS."

"Don't be silly, Ryan. Sexy wouldn't let anyone steal her. Well except maybe for..." the Doctor says, finally turning around but then falls silent as soon as she's facing them "River."

The Doctor looks like all the air has been knocked out of her, Yaz hasn't seen a look like it since their little vacuum adventure and even that had been a purely physical reaction. This time her eyes are almost screaming with the painful mix of grief and something that looks a whole hell of a lot like hope.

"Well now, that's a new look for you Sweetie." The woman who must be River says with a sudden and delighted grin. "I like it."

"River?" The Doctor repeats.

"Though 'steal' is such a strong word." River says lightly and pantomimes the motion of cleaning invisible lint off her clothing.

The Doctor repeat's the name for a third time, her voice breaking on the last syllable when River finally seems to take in the Doctor's poleaxed complexion and gets back to her feet to walk around the controls towards her.

"What is it, my love?" River asks, and because she's still mostly facing them Yaz can see as the transformation takes over the woman's face. There was something very blase about how she seemed just a moment before but now her eyebrows have drawn in concern, and something fiercely protective is blooming in the lines of her face.

The Doctor doesn't wait for River to reach her, in a moment she's dropped the sonic and is colliding with her in a tangle of limbs that take a moment to sort themselves out.

And then Yaz has to look away because there is just something undoubtedly very private about the moment taking place in front of them all.

She still can't help but catch an impression of a desperate kiss and the Doctor pulling the woman so close to her that Yaz thinks letting go of this River would tear the Doctor to pieces.

Maybe because it already had.

The Doctor hadn't really told them all that much more about the family she's lost but it doesn't take much to guess that River was a part of it.

She's wiping a tear away from the corner of her eye when Ryan leaves her side to join Graham. Her eyes follow and her heart twists at the pained look on her friend's face. In front of them is taking place a scene that almost certainly brings back every memory Graham has of Grace.

She takes a step to join Ryan when her eyes catch on the tribbles.

Their bouncing is already reaching past their heads and some of them are almost vibrating with energy. Her eyes widen and she twists around toward the project the Doctor gave them to complete.

It's still not turned on.

"Ryan! How do I turn on the trap?" Yaz yells and then has to turn around again at the sound of tripping and Ryan's yelp of pain.

By the time she's facing him, he's on the ground and the floor around him is covered in jewels, the bag River dropped to the floor when she came in now empty.

"River Song. You didn't!" The Doctor exclaims and though Yaz guesses she's trying to sound exasperated it sounds suspiciously delighted instead.

Yaz narrows her eyes when River throws back her head in laughter.

She's pretty sure she knows how the tribbles got to the planet now. And she was right too. River Song is definitely trouble.


AN2: The first episode was FREAKING AMAZING. I love Thirteen so much. I also love Yaz, Ryan and Graham. But especially Yaz which is probably why I wrote this from her POV.

I hope this was as fun to read as it was to write (let me know if you liked it okay?).

BTW I still have one more prompt I got so keep your eyes out for that one too.