“Who’s Professor Spike?”

“Professor Jonathan Spike is a senior researcher at the university. Only thirty-six and already a professor. I can assure you,” said their mother, heaving a sigh, “that at your age he read books instead of –“

“What exactly does he do at the farm, Mom?”

“He comes once a week to share his huge knowledge with us.”

“And he’s also an expert on orchids?”

“Professor Spike,” said their mother admiringly, “is an expert on anything concerning the natural sciences, and much more. It’d be better for you, Joab and Dina, to follow his example, rather than that dwarfish footballer...what’s his name?”

"Maradona", said Dina with a spurt of laughter.

Joab pinched his sister’s hand with pleasure.

“Ow! Ow!”

“Stop it!”

“You were talking about the professor’s fields of expertise, Mom.”

“There are so many of them, sweetie. To the best of my knowledge, he is, among other things, an expert on orchids, but his real field is...genetic engineering.”

“Whaaat?”

“Genetic engineering,” their mother explained eagerly, “is a science that enables us to change the hereditary features of plants, animals, and even human beings.”

“I don’t understand a word.”

“Well, let’s take orchids, for example. You know orchids couldn’t grow in our garden, because they are not fit for desert life, and –”

“Orchids are not endemic to the desert,” Joab interrupted knowingly.

“Exactly, Jobby,” his mother said in amazement. “Orchids are not endemic to the desert. But, with the help of genetic engineering, we can change that, and maybe some day we’ll have lovely Anatolian orchids in our garden, who knows?”

Joab's eyes suddenly opened wide. “In Hannah’s garden too? I...I...mean in any garden in...in...Di...Dimona, Mom?”

“If you really want to understand,” said their mother hopefully, “you have to know something about genetics.”

“Go on, Mom.”

“All the plants, animals, and human beings in the world are made up of very little cells that can only be seen under a microscope, okay?”

“Okay.”

“Every cell has a nucleus – a central part – that holds the chromosomes. These chromosomes store the hereditary information that is responsible for the features of every living creature, like eye color, the length of your nose, Jobby, or maybe the height of a plant.”

“Very interesting indeed.”

“The chromosomes are made up of a very important complex chemical known as DNA. The DNA molecules are arranged in different patterns, and that’s what determines features. For example, one pattern could mean blue eyes, and another pattern could mean green eyes. Okay?”

“The genetic code,” said Dina eagerly.

“Exactly,” her mother said, pleased. “A chromosome contains quite a lot of DNA, and therefore it’s responsible for many features. But the little bit of DNA in a chromosome that determines each individual feature is called a gene. In other words, the gene is the smallest unit of heredity.”

“Jeans?”

“Not the kind you wear, Jobby,” his mother smiled. “These genes are spelled differently: G-E-N-E. Playing with genes is what genetic engineering is all about.”

“Now I understand,” said Joab, excited, “why Professor Spike is so smart...he probably plays with his own genes.”

Suddenly, Joab jumped away in fear, "What’s this?"

A big bee emerged from the darkness. It had yellow wings and a big white capital letter M in the middle of its red back.

Dina exclaimed excitedly, "Don’t you see, that's one of the bee orchid pictures downloaded from the Dimona Gazette?"

After a quick search they found four more printouts scattered on the bench and all of them had pictures of bee orchids.

"Look! All the pictures are here!" Joab whispered excitedly.

"I bet," said Dina agitatedly, "the professor e-mailed the pictures to the Gazette."

Joab opened a drawer. "What’s this?"

It was a little square cardboard box. Joab examined the box from all sides turning it over and over. Then he opened it carefully. On the bottom lay a small familiar wine-colored flower, crushed.

"That’s the Anatolian orchid we found in Hannah’s jewelry box in the tree," Dina whispered excitedly.

"We already know Inspector Amos brought the flower to the professor for his opinion. Now it's clear he also brought him the bee orchid pictures. And that means,” Joab heaved a sigh, "that we’re not the only ones who noticed the pictures in the Dimona Gazette. What a pity."

"And what’s this?"

There was another bee orchid with a yellowish-green H on its back.

"That’s the sixth and last bee orchid!" Dina exclaimed excitedly. "They know everything."

"You mean," Joab said thoughtfully in the darkness, "the last tick of the ticking bomb."