Barty Crouch Jr?
David Tennant, who also plays Bartemious Crouch Junior in Harry Potter and the Goblet of Fire, plays the 10th Doctor. Barty Crouch is a Death Eater.
Disclaimer. I do not own Doctor Who. I wish I did. If I did, I would not be sitting here typing this. I would be chatting with Peter Capaldi. Doctor Who belongs to BBC. I do not own Harry Potter. If I did, Voldemort would have won. Harry Potter belongs to J. K. Rowling.
Rose grinned at the Doctor as the TARDIS hurtled through the time Vortex. He had seen her reading Harry Potter and had delighted in informing her that it was a biography, not a work of fiction. She had promptly demanded to be taken there. The TARDIS landed with a thud, and Rose flew out of the door, followed by the Doctor.
Their progress was halted by the sight of a bunch of wizards pointing wands at them. The Doctor shoved Rose behind him, and she glared at his back. Bloody idiot, trying to protect me. I don't need protection!
All of the wizards were looking at the Doctor funny. Finally, one of them spoke up, a tall woman with a sharp face. "Barty Crouch Jr?"
Rose facepalmed. Of course the Doctor would end up looking like a Death Eater.
"No, I think you made a mistake," the Doctor was attempting to explain, "I'm the Doctor."
A redhead pushed his way to the front. "Like hell you are! Stupefy!"
Rose tensed for the Doctor to collapse, but the red light turned to golden shimmering dust that sank into his skin. "Oh, brilliant! I'd forgotten that you lot used Artron energy!" he turned his head to Rose. "It's the type of energy that I use to Regenerate." He grinned at the group. "Well, this has been a lovely chat, but we'd best be going now!" He turned and shoved Rose into the TARDIS in front of him.
"Hey!" she protested, "I wanted to talk to the wizards!"
"You still can! It just might be best if we went back a bit earlier. Would you like to chat with Helga Hufflepuff while I catch up with Rowena?"
"Hang on, you mean like Rowena Ravenclaw?"
The Doctor smirked at her. "Yup!"
"You bet I would!
And as the Doctor danced around the TARDIS, Rose smiled to herself.