Over these three years, under the personal guidance of Divine Physician Si, Wu Yun’s medical skills had advanced by leaps and bounds.

Because Divine Physician Si often traveled around, many people who sought him out in Qingzhou could only be treated by Wu Yun. He had the medical books compiled by Divine Physician Si to support him in theory, and in practice, he had so many patients with complex and difficult conditions coming to him. Having cured countless patients with previously incurable illnesses, his reputation rapidly spread throughout the Qingzhou area.

His life had been saved thanks to Yun Chu.

Therefore, as soon as Yun Chu’s letter arrived, he immediately rushed to the capital without stopping.

Chu Yi brought him in, passing through without obstruction into the palace, leading him to the Hall of Mental Cultivation. Eunuch Gao stood guard at the door: “Crown Prince, an hour ago His Majesty coughed up blood again. There was no choice but to feed him medicine to suppress it. Right now, Princess Consort Zhuang is inside attending to His Majesty taking his medicine…”

Hearing this, Chu Yi’s eyes darkened.

Prince Zhuang and Su Ziyue both had problems to begin with.

He pushed open the hall’s main door and strode inside, immediately seeing Su Ziyue sitting at the edge of the dragon bed.

Seeing him enter, Su Ziyue quickly stood up: “Greetings to the Crown Prince. Imperial Uncle just drank half a bowl of medicine and is much better now.”

“Thank you for your trouble, Princess Consort Zhuang.” Chu Yi said indifferently. “You may withdraw first.”

Su Ziyue glanced at the black-clothed man standing behind Chu Yi, set down the medicine bowl, and walked out with her head lowered.

The two palace maids guarding the entrance of the great hall reached out and closed the main doors.

Chu Yi spoke: “Doctor Wu, first check if there’s anything wrong with this bowl of medicine.”

Wu Yun picked up the medicine bowl and smelled it, then extended his index finger to dip a tiny bit of the medicinal liquid and placed it on the tip of his own tongue to taste carefully. Then he shook his head: “It’s just ordinary medicine to dispel cold and stop coughing. There’s nothing wrong with it.”

Chu Yi frowned.

Could it be he was overthinking?

Wu Yun walked to the edge of the dragon bed, knelt down on one knee, and placed his hand on the Emperor’s pulse. After a long while, he said: “It truly is wind-cold symptoms. How strange…”

He released the pulse, stood up, and lifted the Emperor’s eyelids, forcibly examining the Emperor’s tongue coating. His expression immediately became grave.

He spoke: “Your Highness, please remove His Majesty’s inner garment.”

Chu Yi complied, removing the yellow inner robe embroidered with flying dragons from the Emperor’s upper body, exposing his chest.

Wu Yun took out a medicine bottle from his medical kit and applied the white ointment to the Emperor’s chest. Black spots quickly appeared on the skin.

“One, two, three… seven, eight, nine!” Wu Yun’s voice grew heavy. “His Majesty has been afflicted with the Nine Black Gu!”

This was the first time Chu Yi had heard this term. His face filled with disbelief: “Witchcraft gu is a secret technique from the Western Regions. How could it have entered our Great Jin imperial family? Is Doctor Wu certain?”

Wu Yun nodded: “The Nine Black Gu is indeed a secret method from the Western Regions. It includes one male and one female, as well as three small insects. The male and female form a pair, and the offspring gu can control the mature insects. The mother gu requires one month to be planted. One month after the mother gu is planted, only then can there be offspring gu… Based on His Majesty’s symptoms, he’s been afflicted with the gu for at least three or four months.”

Chu Yi suppressed the shock in his heart: “Can this gu be removed?”

“Naturally it can.” Wu Yun pointed at the Emperor’s chest. “The nine small black spots on His Majesty’s chest—every three black spots represent one offspring gu. Killing the three offspring gu will naturally remove the gu poison.”

Chu Yi pressed further: “What about the mother gu? How is that removed?”

Wu Yun shook his head: “I don’t know why, but the mother gu has already died.”

Chu Yi suddenly realized.

The person who planted the gu poison on Father Emperor was Li Jinghua.

No wonder on that day at the birthday banquet, Father Emperor indulged Li Jinghua without limits, even intending to consign Consort Yun to the Cold Palace. It turned out the gu poison was at work.

He frowned: “Since Li Jinghua was the mother gu, then why would Father Emperor, who was afflicted with the male gu, have her beaten to death?”

“This Nine Black Gu has a necessary condition—all those afflicted with the gu must have an emotional bond with the male gu. Whether it’s familial love, romantic love, friendship, or even compassionate feelings, as long as there is emotion in the heart, the gu poison takes effect.” Wu Yun dressed the Emperor in his garments. “Next, I need to take His Majesty’s finger blood as a catalyst to develop the antidote. I ask the Crown Prince to assist.”

His master’s medical texts recorded this Western Region secret technique. It was researched and developed by his master’s master over more than twenty years. The records were extremely detailed, but it required a certain amount of time to produce.

Wu Yun took out a silver needle from his medical kit. Chu Yi picked up the Emperor’s hand, preparing to draw blood.

He was thinking that since emotional bonds were needed for the gu insects to take effect, the range of suspects was very narrow.

Moreover, the one who administered the poison was Li Jinghua. Those who consumed the offspring gu must be people connected to Li Jinghua. With a thorough investigation, they could definitely be found.

Wu Yun’s silver needle had just pierced the Emperor’s finger when suddenly, the person on the dragon bed awakened abruptly.

“What are you doing!”

The Emperor violently pulled his hand back.

Wu Yun only managed to squeeze out three or four drops of blood before the hand broke free.

He quickly secured the blood and knelt down in salutation.

“Father Emperor has awakened.” Chu Yi knelt on one knee. “Your son presumptuously drew blood from Father Emperor in order to develop an antidote for Father Emperor. Please forgive this transgression, Father Emperor!”

The Emperor’s voice was extremely cold: “What antidote?”

“Your Majesty has been afflicted with gu poison. The so-called wind-cold symptoms are actually to cover up the fact of being afflicted with gu.” Wu Yun raised his head. “We need to use the blood of the one afflicted with gu as a catalyst to develop the antidote. Please extend your index finger, Your Majesty…”

“The person who planted gu on Father Emperor was Li Jinghua.” Chu Yi spoke slowly. “She’s dead, and the mother gu is dead too, but there are still three offspring gu. Father Emperor will be bewitched by the offspring gu and act against his true intentions. The poison must be removed as soon as possible.”

“What?!”

The Emperor suddenly began coughing violently.

He remembered that when Li Jinghua was still alive, she had personally prepared food for him once and personally fed it to him. Was that when he was afflicted with the gu?

Although that was the fake Li Jingshu, she had also been with him for thirty years. She deceived him for thirty years and even poisoned him?

In this world, what was left to believe in!

“Cough, cough, cough, cough!”

The Emperor coughed violently and accidentally knocked over the medicine bowl on the table.

The hall door was pushed open as Su Ziyue and Eunuch Gao rushed in one after the other.

“Imperial Uncle!” Su Ziyue lifted her skirt and knelt by the bedside. “Imperial Uncle, your hand is bleeding! Quickly, someone come bandage His Majesty’s wound!”

Chu Yi’s cold, sinister gaze fell on Su Ziyue.

Father Emperor had never been to the An’ding Su family, yet he was extraordinarily different toward Su Ziyue. Moreover, Su Ziyue could speak quite persuasively in front of Father Emperor.

Inside Su Ziyue’s body, there was very likely a gu insect, using Father Emperor’s bit of old affection for the Su family to activate the gu insect.

And Su Ziyue was Chu Rui’s legitimate consort, so would there be a second gu insect in Chu Rui’s body?

And who carried the third gu insect?

He said coldly: “Father Emperor needs treatment. Princess Consort Zhuang, please withdraw.”

Su Ziyue raised her eyes, looking toward the Emperor.

The Emperor covered his chest and coughed a few times, then spoke slowly: “Ziyue will stay to attend to my illness. All of you withdraw.”

Murderous intent surfaced in Chu Yi’s eyes.

Su Ziyue could not be allowed to remain.