"We have to follow him!" Harry, disguised as Thomas, announced.
Draco stood there, disguised as Finnegan, considering his options, looking terrifyingly at where the dog and Weasley just disappeared. "Do we have to?"
Harry gave him a stern look.
"Okay, okay." Draco sighed, and followed Harry who ran towards the Whomping Willow.
"Woah! Careful!" Harry barely avoided a sudden attack by one of the tree's branches.
"The tree can attack you!?" Draco shrieked, and gulped.
Harry pointed has ward at the branches and cast a charm that slowed them down. "That's the same spell Hermione used on the pixies."
"We're gonna die!" Draco, the ever so dramatic.
Now that the tree was not attacking them anymore, Harry and Draco made their way through the tunnel to the shack.
"Ron!" Harry called, in Thomas's voice.
"Dean?!" Harry heard a call back. "Don't-" he started saying, but the his voice got muffled.
"Maybe we should just go back and get a teacher." Draco suggested.
No. Harry barged into the room where the voice was coming from, and the moment he and Draco were in, their wands were grabbed out of their hands.
"Hey!" Harry and Draco turned around just to find themselves facing.
"Merlin!" Draco said, "That's Sirius Black."
Sirius simply ignored him, and looked back at Weasley. "Give the rat to me!"
"Why do you want Scabbers? He's just a rat." Ron objected.
"Give him the rat." Harry stepped forward. Both Sirius and Ron looked at him surprised.
"What?" They both said simultaneously.
"Trust me."
"No, I'm not giving him Scabbers."
"How about give it to me then?" Harry tried to negotiate.
"And do what with him?" Sirius was the one to ask the question.
"We'll take him back to professor Lupin."
That seems to satisfy Black.
"Professor Lupin?" Ron was confused.
"Trust me?" Harry was running out of time. The minute he turns back to Harry, there's nothing he could do to retrieve the rat.
Ron looked at him, and then at Scabbers, and then hesitantly handed him to Harry, who placed the rat in an enchanted bag.
Harry turned to Sirius "You're gonna let us go now, Moony will take care of the rest."
Ron seemed very confused by that interaction. His best friend was casually talking to a Death Eater and a mass murderer. Draco was also confused. Both him and Hermione were on a need-to-know basis.
Sirius agreed. Ron was very surprised by that, but if a dangerous fugitive was letting you go, you don't argue with that.
Halfway through the tunnel, Seamus's hair starts turning blonde, and Dean's skins starts turning brighten. Ron does not take that well.