It was certainly one of the most colourful plants Peri had ever seen. Each part of the stem and leaves was a different shade of blue and green, and the stem split off into three flowers with nine star-shaped petals apiece. Like the rest of it, each petal was a different colour.

"Rainbow blooms," said the Doctor, wandering past, "One of the most popular types of flower on this planet, it would appear." The botanical garden they'd landed in was certainly full of them. Large clusters of the flower grew just about everywhere, mixed in with dozens of other alien plants. It was a nice change from rocks, Peri thought. It was still fairly early in the morning, and they were the only tourists around.

"They're beautiful!" Peri said, snapping a picture with a futuristic device the Doctor had given her earlier. (A phone with a camera in it, although she had nobody she needed to call.) "Do you think if we asked, they'd let me take a clipping?"

"If not, they've got seeds in the gift shop. You could grow your own on the TARDIS. In fact, we could just go buy seeds and start our own garden. Just a little time acceleration and ta-dah! Much more efficient than wandering around here all day."

She rolled her eyes as he complained. It had taken her long enough to convince him to do something she wanted to do, and she was going to take her time and enjoy the gardens. The petals of the rainbow blooms looked oddly soft, yet shiny, and she felt compelled to reach out and touch them. Carefully, she stroked one of them. She had just enough time to register the strange texture before the plant sprayed an enormous cloud of pollen in her face. "Aaah!"

Coughing and sneezing, she backed away and tried to rub the mess out of her eyes. She could feel it caked in her hair and hoped she wouldn't have to cut it; it had taken long enough for her hair to grow out anyway. Suddenly, the Doctor was right next to her.

"Careful!" he exclaimed, "You haven't the slightest idea how any of these plants will react to your biology!"

"I know! I -cough- know. I barely touched it!"

"Of course. Can't keep your hands to yourself, can you?" he dug through his pockets for a handkerchief. "There you go. Ah! Look at this!"

"Can't exactly see much right now," said Peri, rubbing at her eyes.

The Doctor had crouched down to read the little sign near the flowers. "It's all a part of this particular flower's pollination cycle. There aren't any bees here, so it's got to go for the next best thing. You!"

"Me?"

"The pollen sprays onto any passing creature, which will then redistribute it to the other flowers as it ambles about. So you just go like this..." Peri squeaked as he pushed her toward another patch of flowers and started dusting her off at them. "There! Might as well continue the cycle."

"So...is it dangerous?"

"To you? I doubt it. You're still breathing, aren't you?"

"Yes."

"We can rule out an allergic reaction, then." He dragged her over to some more flowers and started shaking out her hair. There was a brief slap fight before Peri took control of the shaking. "All right, all right!" he said, raising his hands in surrender. "You know, if you are starting to feel ill, we could always go back to the TARDIS..."

"Doctor, I'm fine. Besides, a few more hours here isn't gonna kill you."

The Doctor pouted and continued walking down the trail, grumbling. Peri only smiled and followed him. Typical, she thought. She had time to take a few more pictures before she felt the first wave of dizziness. A short while later, she nearly walked into a tree.

"...Peri?" asked the Doctor, startled out of his ramblings. "Are you all right?"

"I think so..." she replied. God, it was hot today. Had it always been so warm? "I need a drink." The Doctor pointed her to a fountain a short way down the trail, but the water didn't make her feel as good as she thought it would. The colours around her were now jarring and painful to look at. She became aware that she itched all over. It took her a moment to realise that the Doctor was talking to her.

"Peri? Peri! I've seen something like this before, and this might be the same thing. How's your temperature?" Without waiting for a reply, he pressed a hand to her forehead. "Hmm...slight fever. Pulse?" He checked; it was racing. Peri could feel her heart pounding in her chest. She took deep breaths, leaning against a tree for support.

So itchy! She was terribly uncomfortable, and oh, she ached...

"Peri!" the Doctor said again, "How are you feeling?" He noticed how dilated her pupils were.

She wasn't sure, so she settled with "Unnng."

Oh, dear. The Doctor was almost certain he knew what was happening to her. His biggest challenge would be getting her back to the ship without her doing anything that would embarrass the two of them. Or worse. "Come on, let's go," he said, gesturing for her to follow him. She took a few hesitant steps forward, rubbing at her arms.

Peri was anxious and dizzy, and now she was starting to sweat. And she had an uncontrollable urge she couldn't quite identify, but she knew she had to do isomething/i to get any sort of relief...

"Doctor,"she moaned, "I need...I need to..."

"Hold on, Peri. Just try to control yourself until-"

His eyes widened as she lunged forward, grabbed him by the shoulders...

...and shoved him to the side so she could get at the patch of rainbow blooms behind him. Frantically, she grabbed as many of the flowers as she could hold and carried them to an empty patch of grass. Gasping for breath, she quickly ripped apart each individual piece of the plants and began compulsively sorting them by type and colour. Blue leaves go in this stack, green leaves go in that one...

The Doctor, recovering from his confusion, came over to watch. "What...oh! Of course! I should have realised that sooner."

"What?" snapped Peri. Blue petal, blue petal, purple petal goes there, pink petal over here...

"It's part of the flower's reproductive system, I believe. In addition to getting other creatures to pollinate for it, this flower also ensures that the seeds will be planted almost immediately."

Red seed, yellow seed, red seed, red seed, orange seed...

"Yes...you're mixing the seeds from each different flower together, and I assume the rest of the plant provides nutrients somehow judging by the arrangement..."

She stopped listening to him so she could better focus on her task. The plants that had looked so gorgeous earlier now looked mind-breakingly obscene. It was a horrible, horrible, jumbled mess, and it made her skin crawl and the only way she could stop it was by taking matters into her own hands. With intense focus, she arranged the seeds into little groups of colours, like a wheel, then stacked the groups of petals around the seeds. Sometimes, it still looked so wrong that she was forced to rearrange things until it looked right. She continued in this way until she had each and every bit of the plant sorted and arranged in a circle.

Finally, she was finished. She sat back, the knot of anxiety in her chest easing.

"Better?" asked the Doctor. Peri nodded. "Good! You had me worried for a few minutes. Well, I suppose we've learned our lesson about touching strange plants, haven't we? Look with your eyes, not with your hands. Peri? Peri, why are you looking at me like...No, what are you...no, stop that! Stop...let go! Peri!"

With a remarkable burst of strength, Peri had managed to rip one of the sleeves right off his coat and started tearing it apart, trying to separate the individual colours. The Doctor snatched it back from her. "No!" she cried, "I have to fix it!"

As she chased the Doctor back to the TARDIS, he made a mental note to not let her buy any seeds.