Yes, the Eldest Princess and the Second Prince were in cahoots. They secretly formed an alliance. The Eldest Princess used the Second Prince to seek benefits for herself and tried to make the Crown Prince ascend the throne. On the surface, the Eldest Princess supported the Crown Prince, but in reality, she was working with the Second Prince to use the Second Prince's power to influence the situation. This scene in the TV series Joy of Life aroused the curiosity and thoughts of the audience.

Yes, the Eldest Princess and the Second Prince were in cahoots in Joy of Life. On the surface, the Eldest Princess supported the Crown Prince, but in reality, she was working with the Second Prince and using the Second Prince's power to obtain her own benefits. The Eldest Princess used her financial power in the Qing Kingdom's treasury to form a secret alliance with the Second Prince and attempted to let the Crown Prince ascend the throne. Their partnership was shown in many hints and details in the play. Although the Eldest Princess supported the Crown Prince on the surface, she had conspired with the Second Prince to use the Second Prince's followers and financial power to influence the situation. This scene piqued the curiosity of the audience.
The Eldest Princess and the Second Prince were in cahoots. On the surface, the Eldest Princess supported the Crown Prince, but in reality, she was colluding with the Second Prince. The Crown Prince didn't have any powerful followers, but the Second Prince had swordsmanship experts Xie Bi 'an and Li Hongcheng, the son of King Jing. In addition, the Eldest Princess held the financial power of the Qing Kingdom's treasury and cooperated with the Second Prince. Therefore, according to the information provided, the Eldest Princess and the Second Prince were in cahoots.
The Eldest Princess and the Second Prince were in cahoots. On the surface, the Eldest Princess supported the Crown Prince, but in reality, she was colluding with the Second Prince. The Crown Prince didn't have any powerful followers, but the Second Prince had swordsmanship experts Xie Bi 'an and Li Hongcheng, the son of King Jing. In addition, the Eldest Princess held the financial power of the Qing Kingdom's treasury and cooperated with the Second Prince. Therefore, according to the information provided, the Eldest Princess and the Second Prince were in cahoots.
[The Eldest Princess and the Second Prince in Joy of Life are in cahoots.] On the surface, the Eldest Princess supported the Crown Prince, but in reality, she was colluding with the Second Prince. There was a relationship of cooperation and competition between them. The Eldest Princess used her beauty to seduce the Crown Prince, and at the same time, she collaborated with the Second Prince to plot a rebellion. The Second Prince was resourceful and more suitable to inherit the Qing Emperor's position. Their scheme was eventually exposed, and the Eldest Princess, Crown Prince, and Second Prince all chose to commit suicide. Thus, the Eldest Princess and the Second Prince were in cahoots.
Fan Xian had his suspicions. Because Zhu Ge and the others had always been covering for the Eldest Princess and the others, Fan Xian had no concrete evidence. After Zhu Ge's death, Fan Xian was in charge of the First Bureau alone. With the full cooperation of the other departments, Yan Bingyun investigated the Eldest Princess 'smuggling of the palace treasury and discovered that the amount of Xinyang smuggling to Northern Qi and Dongyi every year was extremely large. On the surface, the deficit was caused by the Crown Prince of the Eastern Palace, but in reality, the largest amount was handed over to the Second Prince through the Ming family. It was used to bribe officials in court and make friends with the border officials. It made Fan Xian clear that the Eldest Princess was behind the Second Prince.
The eldest princess and the eldest prince had some interaction and cooperation in the play, but no exact ending information was provided. Thus, I don't know how the relationship between the Eldest Princess and the Eldest Prince will develop.
The Eldest Prince and the Eldest Princess were in the same group in Joy of Life. Together, they plotted a series of conspiracies, including using the Crown Prince's banner to do bad things, smuggling activities, embezzling money, and so on. The Eldest Princess had an affair with the Eldest Prince and formed an alliance with him. However, their plot was eventually exposed, causing the Eldest Princess to go crazy and plan to assassinate the Qing Emperor. In the end, she committed suicide. The Great Prince rebelled, but was ultimately defeated and killed by the Qing Emperor. Therefore, the Eldest Prince and the Eldest Princess were in cahoots in Joy of Life.
The Crown Prince and Eldest Princess ended up committing suicide. In " Joy of Life," the Crown Prince and the Eldest Princess had a special relationship. It was not just a relationship between a nephew and an aunt. In order to take revenge on the Eldest Princess, Fan Xian told the Emperor about the relationship between the Crown Prince and the Eldest Princess and planned an incident to expose them. The Emperor's feelings for the Eldest Princess were also a little unusual. After learning of the relationship between the Crown Prince and the Eldest Princess, he placed the Eldest Princess under house arrest and prepared to abolish the Crown Prince. The Eldest Princess secretly joined forces with the Qin family and the Ye family to plan to kill the Qing Emperor and let the Crown Prince succeed the throne. However, after the plan was leaked, it failed. In the end, the Eldest Princess and the Crown Prince chose to commit suicide. The Eldest Princess had another identity. She was Lin Wan 'er's mother.
In Joy of Life, the Crown Prince and the Eldest Princess had an intimate relationship. The Eldest Princess was the Crown Prince's aunt, and the relationship between the two was not allowed in ethics. The woman in the Crown Prince's painting of a beauty was the Eldest Princess. Their affair was eventually exposed by Fan Xian. When the Qing Emperor learned of it, he was furious and banished the Eldest Princess from the capital. The Crown Prince was sent to Nanzhao. The Qing Emperor's feelings for the Eldest Princess were complicated. The Eldest Princess loved the Qing Emperor, and the Qing Emperor was willing to give her power and status. However, when he learned of the relationship between the Eldest Princess and the Crown Prince, the Qing Emperor felt that he had lost control. His trust and pity for the Eldest Princess was also affected.
In the novel Joy of Life, the relationship between the Crown Prince and the Eldest Princess was that of an auntie and a nephew. The Crown Prince was the Crown Prince, the heir to the throne, and the Eldest Princess was the Princess Consort's sister, the Crown Prince's aunt. They had relied on each other since they were young, valued each other, and had deep feelings for each other. Their affair was eventually exposed by Fan Xian. After the Qing Emperor learned of it, he was very angry. He put the Eldest Princess under house arrest and prepared to depose the Crown Prince. After the Eldest Princess learned of the Qing Emperor's plan, she secretly joined forces with the Qin family and the Ye family to kill the Qing Emperor and push the Crown Prince to the throne. However, the Eldest Princess 'plan was leaked from the beginning. In the end, the Eldest Princess and the Crown Prince chose to commit suicide. The search results did not provide any clear information on how the Qing Emperor had found out about their affair.