His eyes were so very old. Hard, brown orbs full of wisdom and light and laughter, holding back so much loneliness and regret. He lived in the moment, so that he wouldn't have time to remember. Oh, there was so much he wanted to forget and it haunted him. The bright, beautiful girl at his side was held at arm's length while she wanted nothing more than to embrace him and keep him forever in her arms. Yes - I saw all of that as I started an IV of normal saline, wide open. His companion insisted on taking his vitals herself, keeping her stethoscope tucked possessively in her pocket. This was a Martha Jones I did not know. This was not the girl who gossiped over coffee instead of studying. She was a harder person than the Martha I knew.

The first time I saw him, he was being half-carried by Martha, into an unfinished part of the new hospital wing. He was gasping for air as Martha dragged me, my wrist in her iron grip, away from the coffee bar in the lobby. And I swear I heard the man gasp, "Nice little shop."

She needed my help, she said, and didn't know where else to go. My own heart was pounding out of my chest as I gathered things out of the supply and grabbed thee 100ml bags of saline from the med room. The O2 tank was the hardest bit to acquire. Luckily, at 7am, the halls were fairly quiet and I was able to get back to Martha and our patient unhindered.

The man seemed unable to speak, his skin like parchment, eyes sunken. Sucked dry, Martha said. Indeed, he looked as though all the fluid had been wrung out of him. He was obviously thin to start; there would not have been much to wring out. Martha's brow was knitted together in deep concern, and I kept an eye on her, even as I started the O2 and the IV. As she wiped his dry forehead with a damp towel, he drifted into a fitful sleep.

Now it was my turn to drag her away, out into the hall. I pulled her into a small supply kitchen.

"What the hell is going on?" I opened a tin of apple juice and put it in Martha's hand. "Who is this guy?"

She drained the cup in one swallow. "The Doctor."

"Who?" I asked, pressing a packet of crisps into her hand.

She tore into them as she spoke. "A friend." She mumbled, "You'd never believe it if I told ya."

"You're gonna have to tell me! I'm about to miss rounds for you!" I handed Martha another tin of juice. "Just what happened to that man?"

I followed her back to the room as she tried to avoid my questions. Her companion was restless, but appeared less drained. He was semiconscious and moaning.

"Loo." Martha darted into the adjacent bathroom and slammed the door. The man on the gurney cried out and I instinctively took out my own stethoscope, deftly opening his shirt. His breath was labored and he was writhing beneath me. When I help the stethoscope's bell to his chest, I heart it. At first, I thought it might be an S4 or a murmur. But placing the bell on the right side of his chest, I had no doubt. Two heartbeats.

His hand was on my arm - reassuring and gentle. I looked up into his eyes, now clear of pain. I couldn't move, the sound of two heartbeats pounding against my ears. I heard Martha's voice behind me.

"Alien. Binary cardiovascular system." Still, I could not tear my eyes from his. Slowly, he lowered the O2 mask. I'm sure he saw fear and disbelief in my gaze as he held it. He stroked my arm reassuringly.

"It's OK. And thank you." He smiled as he passed out.

Martha cried and pleaded and changed her mind a dozen times in the next few hours. She attempted to explain to me what was going on and I had to accept on blind faith (and my trust that she was not bat-shit crazy) that what she said was true. What I knew to be true was that the man we had hidden upstairs was gravely ill, Martha was beside herself, wanting to help him, but fighting some deep internal struggle to stay away, and she was begging me to look after him. Martha was like the little sister I never had. Mentoring her the past few years had taken the edge off my own loneliness, though she could never know that by helping her, I truly had nothing to lose. No one need ever know I was gone, she said. But there was no one to worry about me. There was no one for me to worry about. What was clear was her worry for the man on the gurney... The one who was recovering much too quickly.

As I learned later that, as he was wont to do, he was quick to apologize for the intrusion, and insisted he was fine alone. Knowing Martha as I did, I knew better. She was pragmatic and honest and if she was worried, I knew I should be worried too. Besides, he was weak. In the end, it was our shared desire to see that Martha finished her exams, and if going with this man on whatever danger they both alluded to, then so be it. I left the hospital, for what was to be the last time, and I was to meet the two of them later in the day at the coffee shop Martha and I frequented.

In my apartment, I put what few items I truly felt I needed into my satchel. Journal, iPhone, favorite lipgloss, stethoscope, small med kit, tampons (where would I find more?), a ball of yarn attached to a recently begun sock, clean underwear and small flash drive I kept in a locked drawer of my desk went into the farthest reaches of my bag. I changed into my favorite rugby shirt, sturdiest bra and my favorite blue leather boots. Pulling on my husband's old knit hunting shirt with the leather elbows and pockets, I gathered my courage. I was leaving everything behind. Again. Only my friend Martha would know the truth, and even she would never know where I had gone, only with whom. "Here we go, Edie", I said after pulling my red curls up into a bun. I didn't look back as I walked out. I felt a little insane and more than a little like I was about to be on Candid Camera.

I was a little surprised when I met the Doctor at the cafe and he gave me a once-over.

"Traveling light?" He asked. Martha had already gone, without saying goodbye.

"What else do I need?" I felt complete with my satchel strapped across my body. I was a little worried.

"Not a whole lot. The TARDIS will provide."

With a heavy sigh, I replied, "Well, you need more help and Martha needs to finish her exams. And I need..." We stopped and started at each other.

"Right!" The Doctor pushed himself from the counter. "Allons-y!" He held out his hand and I took it, leaving the cafe and my old life behind.

I hadn't believed Martha when she'd told me about the TARDIS. A big, wooden blue box - the description didn't do it justice. I laughed when I saw it. "Seriously?" I asked. The Doctor was amused at my incredulity. "Wait'll you come in..." He unlocked the skinny door and backed inside, so he could see my face as I entered.

It was like being at the bottom of a champagne glass full of golden bubbles. The walls were effervescent, made brighter by the glowing blue tube rising from what appeared to be a console. The Doctor's eyes twinkled as he watched me. I was honestly more taken in by his delight than the beautiful vessel around me.

"Hmm. Nice." I smiled and feigned disinterest. I walked around the console, dropped my bag near the jump seat and said, "Well, are we going?"

The Doctor frowned. Just as Martha said, he was not used to people taking his beautiful ship for granted. "Really? It's just… nice?" He sauntered up to the console and stroked the railing, as if petting a sad dog. He glanced up at me, eyes full of sorrow.

"No. It's AMAZING!" I jumped up and spun around, unable to keep up the facade.

The Doctor roared with laughter. "Oh yes she is! Just wait!"

"Martha wasn't kidding!"

"Make yourself at home. We have one stop to make before we head out. That last lot nearly sucked the TARDIS dry, nevermind me." He started flipping switches and pressing buttons, and the blue tube in the center of the console came to life. "Need to see a friend about a hydrogen converter." I let him place my hand on a lever, his grin wide. "Ready?" I nodded in response, unable to speak. Our hands released the lever together and the big blue box took flight.