Vin Diesel stars in a new movie this weekend called "Riddick." It's an R-rated action film featuring Riddick who was left for dead on a planet where alien predators roam free. With no other choice, Riddick activates an emergency beacon which sends two groups of mercenaries who both want the same thing, Riddick's head as a trophy.

Here's what our movie critic, Joanna Langfield thought.