Line Walker 2: Invisible Spy

Two boys Ang Tsai and Ah Dee are attacked by abductors in the Philippines. Ah Dee is abducted after he rescues Tsai. The incident hints at a brutal terrorist network that targets children.

The 1987 abduction scene ends with Ah Dee taken by the abductors after the rescue attempt. The incident remains a haunting memory for those involved and hints at a larger conspiracy. It establishes the past that will echo through the police investigation.

In 2019, businessman Miu Kwok Ming drives into a crowd, injuring 18 and killing 5 before colliding with a bus. He commits suicide when the police attempt to arrest him. It is revealed he was being blackmailed by terrorists.

Superintendent Yip and Chief Inspector Ching arrest journalist and hacker Yiu Ho Yee, who claims an international terrorist network abducts children to spy in police forces worldwide. The arrest triggers the creation of a task force to uncover double agents.

An operation in Myanmar and Navarre to intercept terrorists fails. Bill, Yiu's assistant, is killed in a bombing, and a terrorist steals the hard disk while Ching and Cheng pursue.

During the battle, Ching disappears after an explosion, and the hard disk is revealed to be empty. Mr. Tung is eager to obtain whatever information the disk might contain. The pursuit continues as the team suspects internal betrayal.

Cheng returns to Hong Kong and arrests Yiu, suspecting her of giving a false statement. En route to the police station, Cheng's unit is attacked, and only Cheng and Yiu survive.

Another unit attacks the terrorists and captures both Yiu and Cheng. The standoff escalates, and Ching confronts Cheng, hinting at their shared past.

Ching confronts Cheng and, noticing a scar on Cheng's back, reveals that Cheng is Ang Tsai while Ching is Ah Dee. The pair realize they were once part of the same terrorist network and are now adversaries.

Cheng returns home to fetch his daughter Ching Ching and flees. Flashbacks reveal his recruitment by Mr. Tung and Emma being killed while Tung spares his daughter. He later travels to Spain amid the ongoing pursuit.

The ITF travels to Spain with Yiu for the operation to secure Yiu Ho Yee. The plan centers on coordinating a high risk interception over foreign ground.

The safe house is raided as the iris scan is completed. A violent shootout ensues, and Ching informs Tung that the iris video is a virus rather than a capture, complicating the exchange.

Yiu reveals that Mr. Tung’s true headquarters are in Hong Kong, not Spain, and provides the exact bomb locations. Police locate and disarm the explosives, thwarting the terrorists' plan.

Cheng catches up to Ching, and Demon pursues them in a car chase. They crash and fight, ultimately killing Demon by pushing him toward a charging bull. Both Cheng and Ching die from their injuries, but Ching Ching is saved.

With the network exposed, police arrest internal moles and rescue children from the terrorists. The film closes on a note of fragile justice as the case is brought to a close.