Kristen was still amazed that no one thought a random blue Police Box was strange out in the middle of the Paris street. It was the 1800's after all and…

"Welcome to the Opera House," The Doctor said, cutting into Kristen's thoughts.

She followed him out of the TARDIS and found herself in some sort of storage room. There were props and costumes and even scenery strewn around the room.

"Where are we?"

"If I had to guess," the Doctor said, "I'd say we're under Opera House, they tend to store their stuff cellars below the building. There may even be catacombs. They would be fun to explore, don't you think?"

"I don't know," Kristen said. "I want to go upstairs. You can explore during the show, if there is a show tonight. I'm going to go find out."

They easy found their way out of the cellar and emerged into a busy foyer. People were bustling about and gossiping about a ghost and a diva who had just stormed out.

"A ghost? Fantastic! We should help investigate."

"You don't think…" Kristen looked around and shuttered. "There aren't real ghosts, are there?"

"A real ghost is just trapped energy," the Doctor explained as they casually made their way up a staircase. "It's formless, but it sometimes gets stuck in the place where its body perished."

"Excuse me," a sharp voice intoned. "Who are you and where exactly are you going?" They turned to see a rather stern looking woman in all black. She held a cane.

"We were looking for the manager's office," the Doctor replied. "We heard there was a ghost problem."

"The Opera Ghost is superstition, monsieur," the woman said. "A child's tale passed down by the ballet girls."

"Who is she trying to convince?" Kristen whispered.

"Well I am here to help if need be…"

"And you're name sir?"

"I'll trade you," the Doctor countered. He pulled out his wallet of psychic paper.

The woman studied it for a moment. "I am sorry, Inspector, I meant no disrespect. You just don't seem like a member of the police force."

"Ah, the odd clothing. Well my friend and I thought we'd dress for the theatre… to go undercover, I mean. Blend in. This is Kristen, my associate."

"Well you certainly achieved… something. Come this way, I'll take you to the managers' office. My name is Antoinette Giry I'm the Ballet Mistress."

There were, in fact, two mangers of the opera. They had bought the company from the previous owner who had retired. And they seemed to have inherited the Opera Ghost. Unlike the Ballet Mistress, Monsieur Firmin and Monsieur Andre believed the ghost to be very real. Or, at least, some sort of tangible mad man who was blackmailing the Opera for money.

After they had made introductions some relief seemed to wash over the two men. They were at their wits' end and had finally agreed that outside help was needed to fix their problems. And since the Inspector was also a doctor… what better way to debunk a ghost story than testimony from a man of science?

Accidents had begun to happen when the men had struck the Ghost from the payroll. It had been little things at first: props or costumes gone missing, voices coming out of nowhere and mail with no return address showing up in their office.

But once they started to disobey the commands in the letters...

"He wanted his own box," Firmin explained. "It's madness to lose the revenue from one of the best boxes."

"What happened then?" Kristen asked. "You sold it, didn't you?"

"Our paying customers were chased out by a masked man in full evening attire." Firmin sounded exasperated.

"Sounds like your man wanted his identity hidden," the Doctor commented.

"Our Diva has quit," Andre said. "She has been getting threatening letters and then, in the middle of rehearsal, a piece of set fell on her. If we can't get her back our gala will be ruined."

"When is this gala?" the Doctor asked.

"At the end of the week," Firmin told him. "Five days to sort this out or we'll have to cancel a full house! Our patrons will be coming and dignitaries and…"

"You take care of the Diva and we will take of this 'ghost'. The Doctor said.

"Sir… if I may…" Andre began. "Your associate… I didn't think the police force allowed women."

"Oh she's not on the force," the Doctor replied smoothly. "Kristen is a good, trusted friend who sometimes goes undercover for me in places where are too… intrusive. I brought her so that…" an idea dawned. "So that she could join the chorus. Be with the other girls and listen for rumors and see if any of them have a hand in this."

"But Doctor…"

"Can she sing? Can she act? Dance? Will we have to put her on stage?" Andre looked as if he was going explode. He procured a handkerchief and wiped the sweat of his brow.

"She can sing descent enough," the Doctor said. "If nothing else she can stand in the back and mouth the words. It's only until we catch your madman or exorcise your ghost. She'll be fantastic, no doubt."

"If you say so, Doctor." Firmin didn't look so sure.

Kristen looked unsure as well, "I guess I should go practice…"