The urgency implied by the use of all caps suggests that this is an action film, right?
Okay, let's start with the main characters - a woman, her son, her son's friend, an ex-detective, the messenger - and see how they are all connected.
Which gives us "When a woman pays an ex-detective to find her son, an investigation of his best friend reveals a message saying the boys will die in 30 days, the ex-detective only has 3 days left to find the messenger and save the boys."
Now it's just a case of taking out what isn't important and telling the same story in about half as many words. I would start with taking out "die in 30 days", since there is more urgency in "3 days left" and it makes "30 days" pretty redundant.
Good luck with this.
Although, from what I can tell, the woman is the messenger and needs the detective to find the boy and his friends so she can follow through with her threat.