Zhao Wei's version of Princess Zhu Huan, the first step, the part where Wei Zi was cut by a knife for the emperor, which episode is it?

A group of people traveling incognito were watching in a crowded market. Wei Zi and Gan Long met an old couple selling tea eggs. Suddenly, they pulled out their hidden knives and stabbed Gan Long. Everyone in the city has become assassins. Wei Zi saw the emergency and desperately prepared a knife for Gan Long. ...

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