It has been a BIG misunderstanding.

Sam and Dean catched Donna and The Doctor because they thought they were demon's.. Since the TARDIS appeared in the middle of a fight from a case that Sam and Dean were into, and of course that they didn't see the TARDIS because of it's defense system with camouflage, and of course they had to think that Donna and The Doctor were demon's that teletransported there.

It has been quite, far too quiet for The Doctor's like. He and Donna were chained to two chair with some ropes, which seemed pretty hard.. Donna was behind the Doctor and The Doctor was behind Donna, so they couldn't see eachother.. The Doctor was starting to stress out since Dean started to touch his gadgets. Sam was preparing holy water and a book for doing a exorcism and well.. Everything was quiet because they used tape to shut Donna's mouth.

' Who are you and what are those things?! '

Dean exclaimed as he analyzed the Sonic screwdriver of the Doctor.. Oh no, that was the Doctor's most precious gadget.