In the Bacchus area, it is still rainy. Ever since Eric arrived, the damn rain never seemed to stop.

"You seem to have something on your mind?" Caitlyn had already guessed that there must have been an unusual conversation on the phone, and Eric hadn't revealed the full truth to her.

"I'm just worried if our naïve Miss Agent won't find it inhumane to leave her here. Eric avoided Caitlyn's piercing gaze.

The trail was indeed muddy and dirty, and Eric's trouser legs were already mottled with mud, who would have thought that there would be such a dirty alley next door to the poetic and romantic Champs-Elysées. The alley is narrow, with the back doors of the Champs-Elysées hotels, cafes and various storefronts on the left, and the back doors of the various bars and hotels on the other side of the street.

At this moment, a slender figure swayed around a corner of the path. Eric and Caitlyn glanced at each other and immediately ran forward. Sure enough, Chiko was leaning against the wall, rubbing her swollen temples with her hands. As soon as she looked up, she saw Eric and Caitlyn appear in front of her side by side, as if she understood something, but felt that she didn't understand anything.

"Are you alright? Eric wanted to step forward to help Chiko, but was pushed away by Chiko.

"I'm okay, no problem. Chiko flatly rejected Eric's offer.

"It's okay, as an agent, you're physically stronger than normal. Caitlin looked at Qianzi indifferently, but she was very surprised in her heart, she joined the British Special Intelligence Division at the age of 18, and her physical functions have been tested and tempered countless times, but the rookie agent in front of her is just starting out, and after being stunned, she can wake up without external stimulation, and this kind of physical fitness can only be done by talent.

"What about the third puzzle?" asked Chiko in frustration after Caitlin had finished her succinct account of what had happened.

"It should be on you. Eric looked Chiko up and down on a stained shirt and found the corner of a leather envelope in the pocket of her blouse.

"Look for the entrance to Bertha Lane. Chiko opened the envelope and read.

"Gone?" asked Caitlyn.

"It's gone. Chiko handed the letter to Caitlyn, "That's all. ”

Caitlin examined the letter and envelope and did not seem suspicious. But the puzzle is only a short sentence, and they don't know what the other party wants them to seek.

"What do you think. Caitlin asked Eric.

"I don't know. Eric took the letter and examined it carefully, but found nothing out of the ordinary.

The three of them searched separately in the alley, but there was no other place to call it an "entrance" except for the entrance to the sewer and the back doors of the various shops facing the street. At this moment, a black cat jumped down from the high wall. In an instant, a quick image flashed through Eric's mind, but he couldn't see anything clearly, and just muttered, "That brick is loose." ”

"What?" Chiko didn't know what Eric was muttering. But Caitlyn noticed that the black cat had jumped off the high wall, and as soon as her front foot touched the masonry that was a springboard, and the masonry was, as Eric muttered, not very strong, and the black cat had almost fallen off the masonry as soon as she stood on it.

"What a fool!" Chiko reminded dissatisfiedly when she saw Eric's eyes blurred.

"Oh. Eric looked at the figure of the black cat scurrying away, and felt his mind go blank.

"There's something wrong with that black cat?" Chiko saw that Eric seemed interested in the cat.

"It's nothing, I just think it's a stupid cat. Eric immediately opened the subject.

"Come and see. At some point, Caitlyn had walked up to the masonry, and from the look on her face it seemed that something unexpected had been discovered. Eric and Chiko carefully examined the mark Caitlin had found on the masonry, which was very simple: a hollow circle connected by a straight line.

"What does this mean?The direction of the entrance?" Chiko followed the direction of the straight line in the mark, it was a boutique fashion store on the Champs-Elysées, could it be that the entrance was there?

"This ...... There is indeed something unusual. Eric remembered that the mark had appeared several times in the vaults of Rocky Manor.

"What is this? Could it be the company logo of the masonry factory?" Chiko still couldn't see anything special about this simple mark.

"No one will take the symbol of alchemy as their corporate logo. "After the events at Rocky Manor, Eric collected some alchemical materials, including some rare ancient texts.

"I remember that alchemy had a very complex system of symbols. Although Caitlyn recognized this alchemical symbol, she did not have any knowledge of this field.

"Indeed, there are many symbols of alchemy, and they were born at different times and in different places. And this symbol happened to be born in Europe from 476 to 1453 AD. ”

This seems to fit well with the age of the Catacombs of Bacchus to which Leonardo is referring. Caitlin reminded.

"Could it be that Leonardo is looking for that secret that Leonardo is hiding?" asked Chiko.

"It's not logical. Eric went on to explain, recalling everything about the symbol, "Don't forget, Leonardo is still in their hands. ”

"What other message does this symbol point to?" Caitlyn felt a rare sense of anxiety at the thought that Leonardo was still missing, and that she couldn't even be sure who her opponent was.

"This symbol does have a lot to do with a legend. ”

"Who?" asked Chiko eagerly.

"Nicolas Flamel"

Hearing the name, Caitlyn's expression was slightly moved. For Europeans, Nicolas Flamel is definitely synonymous with a legend. He is considered the progenitor of European alchemy, and is said to have created the Philosopher's Stone, the philosopher's stone that all alchemists coveted, and successfully used it to turn mercury into gold.

"The Philosopher's Stone...... Mercury...... Gold...... Alchemy, do our opponents believe that there really is any philosopher's stone that can be turned into gold, and the entrance on the prompt refers to-" This kind of absurd reason can't even be made up by Chiko himself.

Listening to Chiko's chatter, Eric suddenly felt breathless, as if a pair of invisible hands were choking his throat. Eric knocked on the masonry with the mark of mysterious alchemy in annoyance, but when the knuckles of his two fingers just touched the brick, a black and white picture flashed in front of his eyes, although between the electric light and flint, Eric still clearly saw two running figures-

Leonardo and himself.