The hallucinogen that was in Zi Yous mouth was created after studying the books her mother left behind. As for why she wasnt affected by the drug: that was because she already took the antidote before she came to Duke Yongnan fu.

She must be smart this lifetime. No matter where she went, she had to take precautions for all types of emergency situations.

Someone who had died once was more cautious and alert than anyone else. Her body had no less than five or six medicines and multiple hidden weapons.

When she was following Ne Chen earlier, she kept feeling that something was wrong. She couldnt help but be secretly vigilant. So she secretly put the hallucinogen into her mouth.

As for how Zhao HongXiang was so bold to call Zi You into his study, it was because he heard his father telling Ne Chen, Call Youer over here. There are some paintings I want her and Old General Mu to look at.

Zhao HongXiang immediately stopped Ne Chen. He pleaded in a low tone, Mother, take Youer into my study. I have something to say to her.

Ne Chen hurriedly shook her head. No, this is not appropriate. If Old General Mu finds out, he wont spare you.

A trace of a sinister gleam flashed across Zhao HongXiangs eyes. He whispered into Ne Chens ears for a while.

Ne Chen immediately nodded and revealed a ruthless smile.

The scheme the two dreamed up was this: Since Duke Yongnan wanted Ne Chen to call Zi You over, he and Old General Mu must already be waiting in the Dukes study.

Ne Chen was to bring Zi You to her sons study and let her and her son have a private meeting. Then, when Duke Yongnan and Old General Mu impatiently sent her to urge Zi You, Ne Chen would find a suitable time to have someone reluctantly and embarrassedly tell Old General Mu and her husband that Zi You was in her sons study, with her son.