Hermione sat against one wall of control room, her copy of The Standard Book of Spells (Grade 7) open on her lap. She waved her wand quietly, copying the motions demonstrated over the book. Harry stood at the door, looking out the window at the awesome, sparkling depths of space. The Doctor was playing with his yo-yo, making it spin in place at the end of the string before it returned to his waiting hand.

"Do you mind, Doctor?" Hermione snapped after a few minutes. "I'm trying to study!"

"Oh. I'm sorry." The Doctor stuffed the yo-yo back in his coat pocket and leaned against a railing. He soon started wandering around, peering at gauges and examining displays before he soon took out the yo-yo again and continued his trick.

"Seriously!" Hermione pointed her wand at the Doctor. The yo-yo shot off the string and bounced off a wall with a loud clatter, causing Harry to jump and reach for his wand.

"I say, was that really necessary, Hermione?" the Doctor asked.

"Yes, it was. One, I'm trying to study, and this is a rather advanced spell I'm trying to get down. And two, we all know how important it is for us to know how well magic works under these conditions. You never know when we may rely on our wands on some far-flung planet, and I'd rather find out now that they don't work than when our lives are hanging in the balance. Now..."

She pointed her wand and said "Accio yo-yo!" The toy flew to her hand. She stood up and went to the Doctor, taking the end of the string in the same hand as the yo-yo as she tapped it with the tip of her wand. "Reparo!"

"There you go, Doctor. Good as new, if not better. Sorry about that."

"In case you hadn't noticed, Doctor, Hermione takes her studying very seriously," Harry said with a grin.

"That's usually a good attitude to take, Harry," the Doctor replied.