It begins with a scent.

​

Not loud.
Not violent.
Not even noticeable.

 

Just… something beautiful in the air.

 

Four young women.
Different places.
Different times.

​

All found the same way—
seated quietly by a stairway,
leaning against a pillar,
eyes open…
but already gone.

​

No wounds.
No struggle.
No explanation.

 

Only one thing connects them—

 

A faint, elegant fragrance
that no one can identify…
and no one can trace.

 

When the case is handed to the Special Investigation Division (SID),
Commander Yong Tin Kei and his team uncover something far more disturbing than murder.

​

This is not random.
This is not personal.

​

This is selection.

​

A system is at work.
A design hidden inside something as harmless as scent.
A weapon that doesn’t look like a weapon.

​

And worse—
the victims didn’t resist.

​

They walked into it.

​

As forensic science, psychological profiling, and cyber intelligence collide,
SID begins to see the pattern:

​

This is not killing.

 

This is testing.

​

Somewhere in the city,
someone is refining a formula—
not just to end lives…

​

but to control them.

 

And when you finally notice it—
when you finally smell it—

 

it may already be too late.