"I just saved you from intelligent tigers. What else do you need from me?"
"You are not going to get anywhere unless you show your magic skills at tonight's ball."
The Doctor weighed all the possibilities. The TARDIS was locked somewhere in this palace, and guards were everywhere. So it wasn't possible to get anywhere, especially with two scared toddlers. How do they say? "He is wise who is able to choose the least evil." It's better to perform something unusual for this early XIX century crowd and then calmly get away.
"All right. I will. But promise that you're not going to lay a finger upon the children," the Doctor stated, while Jamie and Victoria were clinging to his legs, searching for protection. "Otherwise I might use dark magic, and you do not want that."
"Boom?"
Victoria pointed at the metal rods the Doctor was attaching to the base filled with machinery (from his pockets, of course; needed materials were only there, and he doubted sometimes if that would work.
"No, Victoria. I'm not going to make it all explode. Some... a little bit of... music, that would work..."
Jamie, who was in the other corner of the room which for now was a temporary lab, toddled to them, squashing a small pillow in an unusual way. The Doctor snorted with laughter.
"I'm sorry, Jamie, but it's not bagpipes."
"Bbbbbbbb." Jamie dropped the pillow, upset at the statement.
"I mean, bagpipes could be used if they were exotic. But here they're not. And now please allow me to concentrate."
After the device which the Doctor was making was complete (it looked more like a platform with two antennae than like a musical instrument), he began digging in the piano which also was here. Meanwhile, Jamie and Victoria got bored and began wandering around the place. They understood that the Doctor shouldn't be bothered, because if he fails, they are going to get into a big big trouble, but he would still get them out... Finally childish interest overgrew, and Jamie began tugging on the Doctor's trouser sleeve.
No one was expecting a reflexive move. Even the Doctor himself.
For a moment tense silence filled the place. Then Jamie jumped up and darted out of the room before the Doctor could have said a thing.
"In some time it will be no magic," the strange little man stated, while the present ones were eying him and the item which didn't look like a musical instrument at all. "Well... I know a perfect tune. But first you promise me two things. One: don't try to touch me while I'll be playing. Two: find my Jamie."
"Your what?"
"My Jamie," the little man replied in icy tone. "The little boy who was with me. And if you don't find him, I promise I won't lose my chance."
The group of servants set of to find the boy, while the little man began his performance. At first he reached out to the right stick of his odd 'instrument', and the horrid, unnatural sound filled the hall. He smirked and reached out to the left stick, then began manipulating his hands in the air.
The howling turned into a rhythmic sound, forming a complete tune.
Ooo-oooooo, ooooo-eeeee-ooooo.
Creepy music from the other side, that was clear. Then it turned into a three-fours waltz-like tune, still filled with otherworldly howling.
The little girl clung to the odd man's legs, searching for something with her look but not daring to leave for the real search. And no one moved before the tune was over. Only then the doors opened, and a servant walked in, holding a wiggling child by his hand.
"I hope you're satisfied," the little man said, lowering his hands. "Jamie? It's okay, it's over. We're going to get back to the..."
But the boy hid his face and whimpered. Having forgotten about this howling item, the little man walked up to the servant keeping him in place, crouched and reached out to the child:
"Jamie, do you understand that I didn't intend to strike you this way? I would've never done that on purpose."
The boy peeked at him with one eye, then unsurely toddled two steps forward, not knowing if he should be prepared for a counter-attack.
"What are you staring at?" the little man asked, eyebrows arched. "Heard me? Allow me to leave you peacefully... and don't try to use those," he pointed at the odd musical instruments with his thumb, "for wrong purposes. If you do, I will find you."
Jamie was obediently walking behind the Doctor, but, unlike Victoria (who was ready to bounce with glee, but the manners of her adult version were not allowing her to do so - and slowly giving up), he seemed to be indifferent to what was going on. Only when the TARDIS doors closed behind them, he darted into the corner and grabbed his "safety knife".
"Another grudge, Jamie?" the Doctor asked, tugging on the launch switch. "I've already told you I didn't mean anything wrong. Was nervous. You saw what was going on there..." He sighed. "Do you even understand what took place?"
Jamie blinked.
"Listen up, I promise I will never hurt you on purpose. You know that well. And this knife does not influence any thinking matter, you know that even better."
"Doka tyad," Jamie replied.
"Tired? Of you? Nonsense! Promise me that you will never even think about this, Jamie."
The boy made a couple of unsure steps towards his guardian.
"I think I know what you need." Before the little one could've resisted, the Doctor scooped him up, giving him a generous cuddle. A second later Victoria joined them as well. "There we go."
"Oooooo-eeeeee-oooooo," Victoria hummed, imitating the sounds which had terrified the XIX-centurers. "Oooooo-eeeeee-oooooo."
"That's called a theremin," the Doctor informed and led them to the room filled with all kinds of musical instruments. "One easy thing to do. Look, it creates the electromagnetic field, and you make it sound differently with moving your hands."
"Ooooooo," Jamie reacted, grabbed a pair of cymbals from the shelf he could reach and began rotating them. He seemingly wasn't offended anymore. "Ooooooo."
"Flying saucers, you mean?" The Doctor chuckled. "Oh yes. And flying pans too."
A/N: Yes, theremin is a pretty much alien-sounding instrument (and it is the one used to perform those "oo-ee-oo" sounds in Doctor Who musical theme). Another musical theme in which it is used is from the series Midsomer Murders.