Trinity of Shadows

City Councilor Yang Chi Hsiao is shot in his electoral district. Tze Wei rushes to the scene immediately and makes an unexpected discovery.

Tze-Wei takes on the task to safeguard Chi-Hsiao and identifies the shooter as a wanted criminal. Meanwhile, Nicole’s neighbour, Ching-Yao, discovers a body while hosting his friends.

The body is identified as Jia-Jia, a young woman linked to Chi-Hsiao. While Tze-Wei and Chia-Hao suspect a police cover-up, Chi-Hsiao is already one step ahead of them.

Tze-Wei and Chia-Hao decide to work with Chi-Hsiao to investigate Ming-Chieh. When he is released due to a lack of evidence, Chia-Hao is infuriated, as his grudge is driven by personal reasons.

Tze-Wei and Chi-Hsiao continue to investigate Jia-Jia's murder. They receive a critical tip by chance. Meanwhile, Chia-Hao continues to look into Ming-Chieh on his own.

Tze-Wei believes that Chia-Hao’s disappearance is connected to Ming-Chieh’s kidnapping. Acting ahead of the other police officers, Tze-Wei tries to get ahold of Chia-Hao but to no avail.

Chia-Hao forces Ming-Chieh to confess his involvement in the murder three years ago while Tze-Wei and Chi-Hsiao attempt to talk Chia-Hao into letting Ming-Chieh go.

Investigation into Jia-Jia's murder is still ongoing but no one knows that Ta-Dong holds the answer. Meanwhile, Ta-Dong’s plan to target Tze-Wei appears to have something to do with Chi-Hsiao.

Hu Ta-Dong kidnaps Tze-Wei but refuses to reveal his motive. Tze-Wei eventually escapes, but her escape turns her into a murder suspect: She is accused by Ching-Yao of killing his classmate. In the middle of his tense election campaign, Chi-Hsiao insists on helping Tze-Wei. Unbeknownst to him, they have a connection in the past that cannot be untangled.

Chi-Hsiao continues to quietly help Tze-Wei. He also wants to figure out why Ching-Yao would frame Tze-Wei. Although he's unable to convince Ching-Yao to tell the truth, the misunderstanding between him and Tze-Wei is finally resolved. The two discover that Ching-Yao is threatened by Ta-Dong. It seems that everything is being controlled by Ta-Dong...

An unexpected death causes Tze-Wei to be even more determined to arrest the suspect. Meanwhile, Chi-Hsiao's father is displeased with his relationship with Tze-Wei and decides to take action.

Tze-Wei finally finds out who Chi-Hsiao's biological mother is while Chi-Hsiao locates Tze-Wei’s missing mother. They confront their demons and resign to the tragedy caused by their parents.

When Tze-Wei visits her grandfather at the nursing home, she runs into Ta-Dong. In that moment, Chi-Hsiao also shows up with Tze-Wei's mother. The time has come for Ta-Dong to seek revenge.