(Comedy:) When a narcissistic matinee idol gets lost in in the highlands of forested Africa with his co-starring love interest, he must get them both to safety before the legendary Congo Kong slaughters them.

Thanx, dpg.
Your comments made me re-think the story line, and I've come up with a new logline, which I'm entering separate from this one.
...............j

What's so funny about vicious poachers? Seems to me that having them to add depth comes at the expense of subtracting from the comedy.

What are the actors doing in Africa - what was their original objective goal-- and why would poachers be after them? The logline reads like a coincidental collision; 3 parties go bump in the jungle; hilarity ensues.

Well, maybe it does, but in modern comedy scripts there is usually a thread, a common denominator - theme, MacGuffin, schtick -- something that ties the characters and action together. Is there one?

And how about if I add "vicious poachers and" so it reads:

When he and his co-star get lost in Africa's deepest forest highlands, a narcissistic matinee idol must guide them to safety while being stalked by vicious poachers and a ferocious giant gorilla.

(I just got the idea of the poachers to give it more depth than being a mere comedic King Kong rip-off.)