This is a poem Kara writes after she is left behind. She's a prisoner in a secret facility having her powers tested. Basically, she's trying to figure out if her times with the Doctor were even real.

I could swear I remember

The way it felt, traveling together

So many places we were going to go

So many things you said we'd do

I could swear I remember you

Your untidy hair, that damn grin

The suit and long brown coat

Your eyes, the feel of your mind

I could swear I remember it

The TARDIS and its many rooms

Her thoughts, the power of her

She only looked like a blue box

I could swear I remember then

The running, lots of running

Spinning through time and space

Laughing until I thought I'd die

I could swear it was real

Plastic-faced aliens that took me

A rescuer who needed rescuing

A man with a nightmare inside his head

I could swear these memories are true

The telepathic aliens with those head things

Chinese takeout gone horribly wrong

Swimming in an alien ocean

I could swear you were there

My memories, they're so vivid

I can still smell that smell you had

Like everything and nothing at all

The giant teddy bear next to me

The one we got at the circus

It's all I have left of you

If you were even real at all

The sting of a needle in my arm

The ache as they test me

The bleeps of the machinery

Remind me of what is real

They say it's all in my head

They say I've been here for years

I don't remember those years

But I remember you

No one knows I'm here

Alone in this so-called hospital

Here I'm surrounded by medical personnel

But not a single one of them is my Doctor.