Before getting married, the mother-in-law knew that the father-in-law had an unforgettable first love, and their union was just a family alliance.

The father-in-law promised that he would abide by the spirit of the contract and likewise required the mother-in-law to keep herself pure.

To adapt to each other, they began preparing for pregnancy only three years after their marriage, and their relationship as a couple gradually improved.

However, the father-in-law broke his promise and had an affair during the pregnancy, having a one-night stand with his already-married first love.

By a stroke of luck, the mother-in-law learned that the first love had returned to her parents' home with her child after separating with nothing.

That child was named Dai Qingshu, and the character "Qing" in the name was particularly glaring.

The mother-in-law grew suspicious and secretly had someone obtain the child's hair for testing, which confirmed that the child was father-in-law's biological child.

After dropping many hints, the mother-in-law was certain that the father-in-law was unaware of his illegitimate son.

A bold and malicious plan was born.

The mother-in-law bribed the father-in-law's close associates and bodyguards, preemptively choosing the identification agency, repeatedly forging paternity test certificates between him and Dai Qingshu.

So, Dai Qingshu and the father-in-law each insisted on their own version of the story.

Thus, the father-in-law unhesitatingly killed Dai Qingshu to accompany Gu Qingyu in death.

The mother-in-law only needed to tell the father-in-law the truth when he was at his most vulnerable, effortlessly shattering his mental defenses and causing his demise.