Although the specifics of chess can be complicated, the overall objective is simple:

Protect the King at all costs.

After giving up a dangerous life of dodging bullets and leading covert operations, the only thing Choi Areum is worried about protecting is herself from eviction.

However, after a fateful reunion with her famous partner in crime (with whom she has some serious unresolved history) and a forced return to the organization she'd run away from, her list of worries instantly multiplies. 

Three years ago, she was being told that she was one of the most promising agents of her time.

Now, according to some unknown psychopath out to kill her, she is nothing more than a piece in a game.

But she isn't just any piece

Choi Areum is the Queen.

With this label instantly comes the expectation to do anything and everything to protect the King for, although they have the same abilities, it isn't game over when she gets caught; it only is when he does. 

And who is it she's expected to risk her life for?

The boy who makes her blood boil more than any other

The only person in the world she can trust

Her partner in crime; her other half

Jeon Jungkook is the King.