The preparation stage was long and tough, but the execution was surprisingly easy - after throwing some spicy s*it into the fan, FL simply had to watch how the toxic bully clique basically destroyed themselves.
FL was bluffing a lot though, her plan was not bulletproof, but she counted on rotten nature of those involved and they did not disappoint.
And way too many convenient events, serendipitous to FL's plan, also helped smooth the execution by a lot.
Still, it was satisfying to watch the main plot unfold, how FL's bullies ruined themselves and got what they deserved.

On the minus side, I'm also of the popular opinion that romance was not necessary here. Those two actors just didn't mesh together, and later reveals about ML and his fixation on FL kinda creeped me out. I'd even go so far as to say it ruined what should have been a catharthic ending with that unfinished side plot about ML's revenge.

Most of the cast did a splending job, especially the actress playing spy/housewife, she has some range, I think her role was way tougher to play than FL.
The main evil bitch was great too - loved to hate her.
Her businessman husband was also awesome, he had a lot of presence even though he was just a side character.
Some bad guys were overacting too much though, especially FL's mother.
FL was ok for playing a deadpan character, but I think a bit younger actress may have been better. ML looked like he was miscast, tbh.

Anyway, a good show overall, definitely one of the best revenge dramas out there. No cringey makjang or extreme violence like in some other revenge dramas out there that made me drop them.