Author's note: yeah, I know that the trip to Hogwarts doesn't last through the night, but I needed it to fit in with my story. Thanks for reading and review, please!

Sirius POV

"Oh my God,"

I quickly turned to Remus and protected Katrina with my arms. Right on time, one of the few clouds in the sky shielded the moon from view. Remus looked very sick and he was shaking all over, but had not yet turned into a werewolf. Katrina whimpered behind me. I kicked James, who was nearest to me, with my left foot.

" 'Sa matter?" James mumbled groggily. I jabbed my head in the direction of Remus and saw James look almost as shocked as Katrina.

"Wake up, Wormtail." James shook Peter who was snoring loudly next to him, and he awoke with a start.

"What's happening?" Peter said sleepily, with a hint of nervousness in his voice.

"Remus," James said, eyes alert. Peter took one look at Remus and let out a cry of horror.

"Calm down, Peter. Just transform and you'll be safe. Go hide in a hole or something."

Katrina said her first words in that conversation quite abruptly.

"Transform? He's an Animagus?" Katrina looked startled.

I nodded, but James took no attention of the fact that Katrina was in the room also.

"We better transform too, Sirius. We don't have much time. Who knows when that cloud will move over and show the moon again? How are we going to keep him in this compartment? We can't let him out, that'll cause a big scene. And we need to get rid of our stuff so he doesn't rip 'em to bits. And what about Katrina?"

"You two are Animagi, too?" She sounded condemning.

"Yeah, we are." I said, pacing the floor, getting slightly annoyed. Why should she care if we're Animagi?

"Brilliant! What do you change into?" Katrina said, her eyes glowing with excitement. I stopped pacing and looked up at Katrina, surprised. James also suddenly stopped trying to lug his suitcase, which didn't seem to want to move, out of the cubby and looked up at Katrina. He was probably also thinking along the same lines as I was.

"Um…er…." James looked at me for help.

"Er…I turn into a dog, and James turns into a stag." I said uncertainty.

"Yeah," James ran his fingers through his hair, as if in deep thought.

"Okay, now back to business – hold on, - how did you know that Remus was a werewolf?" James looked seriously at Katrina.

" That's a long story, I'll tell you later. We should start thinking about keeping him in here right now." Katrina said quickly.

"Oh, right." James sat down and put his head in his hands.

"You should probably get out, Katrina. Remus isn't safe around humans." I said.

"Right, right. Where do I go? I can't just stand out in the aisle!"

"Well, you can't stay in here. Tell you what, Wormtail," Peter jumped at being called upon, "You stay with Katrina outside. Keep her in this aisle but away from this compartment."

"Here it comes," James looked out the window; a sliver of the moon was revealing slowly as the cloud moved away. He transformed into a stag and Katrina let out a squeal of delight.

"Okay, out the door, Katrina, You too, Wormtail." I turned into a dog as Katrina let out another sound of amazement and I felt a sort of happiness in me. I pushed the door close behind them and then waited anxiously for Remus to change.