Disclaimer: I do not own Doctor Who. This story is based on the Doctor Who characters and universe.

Science assassin: Chapter four

When the Doctor and Donna reached the hotel entrance, they found it full of uniformed police, all facing them with guns.

"Well done miss," one of the officers said, looking at Wanda.

"My pleasure." Wanda pocketed her gun and smiled. "I found them rummaging around the bins, looking for the poisoned food so they could remove all traces of it."

"That's not true!" exclaimed the Doctor. "We wanted to analyse the poisoned food, but it was already gone from the bin."

"Also," continued Wanda, ignoring the Doctor. She was doing quite a bit of ignoring these days, and was enjoying it immensely. "They claim to be working for the victim, but after private questioning I discovered that he has not tutored or mentored anyone for the past 3 years. They were lying!"

"Well, well, well." The police officer in charge turned to the Doctor and Donna. "Who are you really? Thieves in disguise? Bandits waiting to rob a poor scientist of his plans and inventions?"

"Chief Inspector Smith and assistant Donna Noble, employed by the detective agency of Scotland to investigate a rumour of possible murder around the international science committee." The Doctor whipped out his psychic paper, winking at Donna. She sighed in relief, knowing that the paper showed anything the Doctor wanted.

The police officer was staring in surprise, his mouth hanging open. The Doctor turned, grinning, to show the paper to Wanda. Her dark skin had turned a deathly pale, and she stared at it, wide eyed. For the first time in her life she was unable to keep her composure. "I...I..." Her voice was shaking, and she stepped back. Suddenly, something seemed to snap inside her, and she stood up straight. "Excuse me." Her voice was back to its normal coolness. "I must go now." Swinging round, she walked off briskly, leaving a victorious Doctor behind her.

"Sir!" The police officers stood up straight. "Anything we can do sir?"

"No thanks," said the Doctor in a victorious voice. "I am sure I have everything under control now, with her," he added, pointed to the retreating Wanda. "But there is one thing I need. Can you get me the results of Mr Lewis Klyne and his current status?"

"Yes sir!" The officer saluted and walked off, his troop following, holding their guns straight over their shoulders.

"Well, that went well," said the Doctor, pleased.

"Thank goodness you have that psychic paper," replied Donna.

"I know, good stuff it is." The Doctor pocketed his paper. "Come on! Let's do some interviewing."

He and Donna made their way back to the dining room, where the scientists were still chatting and sampling after-dinner mints.

"Sometimes scientists can be the stupidest people in the world," commented the Doctor. "There has just been a case of poisoning and yet they unsuspiciously eat after-dinner mints."

He walked over to an elderly man who was talking with the young scientist who had spoken to Donna at dinner. "Good evening gentlemen," The Doctor said, sitting down.

"Oh, good evening." The elderly one held out his hand. "Sir Robert Grodger at your service."

"Pleased to meet you, Sir Robert. I'm the Doctor." The Doctor shook hands politely. "And you are?" He turned to the younger man.

"Arthur Dales." He also shook hands.

"I was just wondering how you two were chosen for the committee. It must have been a great honour." The Doctor took out a notebook and brandished a pencil in the air, as if to take notes.

Arthur Dales eagerly plunged into his story, explaining every detail of his food invention. The Doctor popped on his glasses and scribbled notes. "I see, I see. Thank you very much. And you, Sir Robert. What, er, great scientific discovery did you make?"

"I," said Sir Robert, "discovered the motroids."

The Doctor raised his eyebrows in interest. "Very interesting, very interesting indeed." In his effort to appear a Scottish detective, he lapsed into a bit of an exaggerated accent, rolling the words around in his mouth. "And when did you first discover these aliens on Mars?"

"Before I continue, I must ask what your accent is. Is it Indian?" The old scientist looked quite confused.

The Doctor quickly switched back to his normal voice. "Er, no. It's Scottish. Anyway, as I was saying, when did you first discover these aliens?"

"Let me see..." the scientist frowned thoughtfully. "Many, many years ago. I was part of a team of scientists chosen to visit Mars for the first time, and was honoured to be allowed to walk on the surface. We didn't expect to find life, we only wanted to study the earth and collect rock samples. But there, I discovered a tunnel, and following it, came upon the motroids. I spent the next 10 years studying them and teaching them to talk, because they only communicated through noises. Eventually, when we could communicate fluently, humans invited them to earth, in return for study on Mars and access to the special dust there, which is very useful in medicines."

"Thank you." The Doctor put away his notebook and stood up. "Now, do any of you have any idea who could have poisoned Lewis Klyne?"

The answer was no, so the Doctor politely retreated. He met up with Donna, who had quickly spoken to the other 7 scientists. "Discovered anything?" he asked.

"Well, let's see. Mr Mckenzie made eye drops to fix eyes which need glasses, Stan Apricot discovered that highly concentrated apricot juice mixed with something can fix broken bones, Hue Hew discovered a new element, Mr Long invented the bubble cars, Gus Roland made microscopic hearing aids, Fred Colle assisted in the motroid projects, and Mr Prumble made a start on teleportation devices."

"I meant, did you discover anything about the poisoner?" asked the Doctor.

"Oh." Donna thought back to her quick conversations. "No."

"That was all I needed to know." The Doctor picked up a telephone. "And now I would like to know more about the poison."

He dialled a number and was soon talking to the same police officer who had wanted to arrest them earlier. After a long discussion, the Doctor hung up and turned to Donna.

"Very simple. Rat poison was slipped into the man's meal. He's quite ill, but is expected to eventually recover completely. It's quite ironic really, since Louis Klyne was famous for making a poison which killed rats if they smelt it."

"Is that what he was chosen for?" asked Donna.

"No, he also helped out on the motroid projects. Anyway, getting quite late now. How about some rest and more problem solving tomorrow?"

Donna yawned, and suddenly realised how tired she was. She was also quite hungry.

"I am tired," she said, "But I'm starving. I didn't exactly have the heartiest meal. Is there any poison free, non squishy food available?"

The Doctor grinned, and handed her a few silver notes, each reading 100 units. "Go and buy something from a store. I'm going to the TARDIS to pick up some equipment. See you tomorrow."

Donna took the money and made her way along the streets, looking for a store, while the Doctor made his way back to the TARDIS. At that same moment, the poisoner sat in a small room in the hotel Noble, carefully plotting their next move: TO REMOVE THE DOCTOR.

More to come...

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