Film-maker Rob Reiner has slammed big-budget Hollywood movies dominated by special effects and techno-wizardry, insisting the secret of success is good writing and casting.

The When Harry Met Sally director says quality actors and an intelligent script can make any film work.

He says, "Scripts is 80 per cent, casting 15 per cent. Get the right script and the right people in the right parts and you're pretty much home.

"I'd have to point the camera away from the characters to screw it up."