On Christmas Eve a failed Hollywood agent?s suicide attempt is interrupted by MARLON BRANDO?s ghost who informs him that he might as well end it all? OR he can try again. And again. Until he gets Christmas (and his life) right for once.

You can condense the opening to “When a timid Hollywood agent’s suicide is interrupted by Marlon Brando’s ghost …”

You need to get creative with how you shorten it down, essentially. The above might not be the strongest, but it covers the key ideas you were conveying. Still; your character’s goal is unclear. Is your film some sort of Christmas Carol meets Groundhog Day scenario?

Instead of saying “worst” talent agent, describe the flaw that causes him to fail at his job and life. Is he egotistical? Chauvinistic? Timid?

One of things that makes Groundhog Day’s goal – repeat the same day until he gets it right – work is that we understand what the protagonist’s flaw is very clearly, and as an audience can extrapolate that he will need to fix this before he is allowed out of the time loop. So I would recommend making your protagonist’s flaw VERY clear, if you’re going to suggest the goal is something as difficult to visualise as “getting life right.”