An ex convict must rescue his granddaughter from sex traffickers who might be a part of a prostitution ring.
I’d get rid of the “who might be a part of a prostitution ring” part.
INTENTION: rescue his granddaughter.
OBSTACLE: sex traffickers.
It lacks a hook that separates it from “Taken”.
– An escaped convict must rescue his granddaughter from the same sex traffickers, whom he inadvertently helped to break free. (I’m not sure if the hook/twist is strong enough here.)
– When his granddaughter is taken by sex traffickers, a convict, a former FBI agent, is given 24 hrs to find the men responsible. (We’ve got a ticking clock/deadline.)
– When his granddaughter is taken by sex traffickers, an ex-con returns to his old ways to find the men responsible. (Very tired and cliche.)
– An ex-con must return to prison and kill a criminal mastermind or else sex traffickers will kill his granddaughter.
(This is similar to BRAWL IN CELL BLOCK 99. Which may I add, is a pretty cool film ha.)
Admittedly, none of these have that strong hook – but I’m spit balling.