"You're joking?"

"Nope."

"Doctor, you're taking me to a planet full of giant sponges?"

"Yep!" He wouldn't stop smiling. It was mildly infuriating. "Start you off slow. Sponges, nice and easy." He throws a switch and pushes a few buttons. The TARDIS started shaking, and I fell against the center console-thing.

"And, there!" I heard a banging sound, and suddenly everything was still. "Lissa?"

"Mmph." I pushed myself up, trying to ignore the sharp pain in my side from falling on some strange object protruding from the center console. "What?"

"Come on, let's see then!" He offered me his hand, and I shook my head.

"You're ridiculous."

"Thank you. Now, come on!"

I smiled in response, taking his hand. He pulled me to the door, throwing it open and stepping out. I followed him out, looking around.

"This…is not Porifera." The Doctor frowned. "Something's not right."

"We're on the wrong planet?" I said. I could feel my knot of anxiety in my stomach tightening.

"Yeah, that happens sometimes. TARDIS has a mind of her own. Tricky girl, she is."

"The TARDIS is a girl?"

"'Course she is. What else would she be?"

"A spaceship?"

"No! And yes. Anyway, not the chief concern. Where are we?"

"You don't know where we are?"

"Then you should leave!"

The Doctor and I spun to find a man holding a spear and a reflective shield. He narrowed his eyes at us. "Who are you and what are you doing here?"

"Where is here?" the Doctor replied.

"Planet Perseus." The man's response was curt. At first I thought he was just being rude, but when I looked closer, I could see the telltale signs of fear. It was like the Doctor had said. Something was wrong indeed.

"Planet Perseus, eh?" The Doctor frowned. "I know that name."

"He's the hero who defeated Medu—"

"Do not say that name!" The man lowered his spear at me, and I blanched.

"I'm sorry," I mumbled.

"I will ask you once more, who are you? What is your business here?"

"I'm the Doctor and this is my companion," the Doctor responded, casual as could be.

"You're a doctor?"

"Well, yes and no."

"Please, can you help us?"

"It's quite possible."

"Follow me." The man turned away from us to lead the way before turning his head back. "But stay close."

"Doctor," I said, looking at the stone surrounding me, "are we underground?"

"Possibly. The surface of this planet may not be habitable, so perhaps to these people this is the surface."

"Is he human?"

"No."

"What year is this?"

"Don't know. Not too important right now. What is important is whatever has this poor man so scared."

"Yeah," I said. And why he wouldn't let me say Medusa.

I wasn't prepared for this. "Everyone, I've brought a doctor!" The tent was full of…aliens…lying under blankets. I was no judge of alien illness, but all of them looked sick to my human eyes. The man leading us pushed a button on his watch, and I gasped when he suddenly became just like the aliens lying around me.

He turned to face us, and I restrained a squeak of slight revulsion. "Doctor, please come and see."

"Of course." The Doctor and I followed the alien to one of the sick ones. We knelt down to the stone ground, and the Doctor put his hand to the skin of the sick alien. "Cold," he said. "Too cold."

"That's a side-effect." The alien reached down and withdrew the blanket from his comrade. I gasped, my stomach lurching.

"S-stone," I said.

The entire lower half of the alien's body was solid gray stone. It looked like the stone had been making its way from somewhere like a foot, and it just kept spreading.

"What did this?" The Doctor touched the stone alien, his brow furrowing.

"They are called Medusiae," the alien said. "Their gaze turns those who meet it to stone."

"Like the myth," I whispered. "But I thought the gaze would turn someone to stone completely. Why is this creeping?"

"These here," the man said, gesturing to the aliens I could see, "caught a glimpse of a Medusiae in something reflective. Something polished and reflective would have turned them to stone immediately. This poor fellow saw one in the reflection of someone's eye. The other…was lucky. He became stone on the spot."

"Lucky?" I gasped, horrified.

"This…is pain. Agonizing pain." As if to prove his point, I heard a shriek. The alien sprang to his feet, running to another form on the floor.

"Doctor, what are they?" I whispered.

"Perseans."

"Did you make that up just now?"

"Yep."

"Great."

"Doctor, please!" The Doctor leapt up, heading toward our alien escort. I turned to face the alien before me, fear making it impossible to move. The stone, however, felt no such restraint. I watched it creep another inch, and I let out a little exclamation.

I got to my feet, wanting to flee. It took me a moment to calm myself, which was a miracle in and of itself. I pulled the blanket back over the alien at my feet (Persean, ha!), and walked over to where the Doctor was kneeling.

This one looked like a girl alien. She looked pretty rough. The stone was already up to the top of her chest.

"This is my daughter," the alien said, looking down at the girl before us.

"Daddy," she whispered. I felt my heart break clean in two. There was so much sadness in that word.

"Yes, my angel. It will be all right." He took her hand, and a tear fell from his strange, alien eyes.

"I just want it to stop hurting!" she cried, and I flinched.

The Doctor took something out of his coat pocket. It glowed and made a strange whirring noise as he ran it along the length of the girl.

"What's that?" I asked.

"Sonic screwdriver."

"A sonic screwdriver?"

"Yep. Good for all sorts of…things. It's complicated."

"Everything is with you," I muttered. I turned to the other alien. "Do you have a name?"

"Malgam," he said, looking up at me.

"I'm Lissa," I said.

"All right, introductions are lovely, but we've got work to do." The Doctor got back to his feet, looking around us.

"Doctor." Malgam squeezed his daughter's hand once more before standing. "Can you save my daughter?"

"No."