After an elaborate conspiracy conducted to lure him in, a retrenched detective discovers a cult that promises him riches but the cult has more in store for him than what he bargained for. OR A desperate ex-cop joins a cult in order to save his family but the cult kidnaps his daughter for ‘slaughter’. He has to save her even if it means losing his own life.

A "retrenched detective" -- what does that mean?

"...joins a cult in order to save his family..." ?-- save his family from what?

And it's not the cult that ?kidnaps his daughter -- it would be the cult leader who orders his followers to kidnap her. ?The logline should clearly ID the antagonist.

Why does the cult leader want to kill the daughter?

I don't understand what the motivation is for either the protagonist getting involved or the antagonist wanting to kill.

What Richiev suggested.

Your second logline option is better but lacks coherence - Richiev fixed it.

"When an Armageddon cult that worships?Moloch kidnaps his daughter, a retired detective with a certain skill set must traverse the dark world of Neo-Paganism in order to save his daughter from being sacrificed to the fire god."