Betrayed by his own kind and left for dead on a desolate planet, Riddick fights for survival against alien predators and becomes more powerful and dangerous than ever before. Soon bounty hunters from throughout the galaxy descend on Riddick only to find themselves pawns in his greater scheme for revenge. With his enemies right where he wants them, Riddick unleashes a vicious attack of vengeance before returning to his home planet of Furya to save it from destruction.
This movie contains 40 potentially triggering events.
There is an alien hyena dog creature that is computer generated. It is VERY dog-like in how it follows and protects Riddick. When Riddick is trying to negotiate with the idiots he is fighting, they try to attack him when he is walking away, and the dog creature attacks them to help him. The dog creature is on top of one of the main assholes, and the guy manages to grab a gun on the ground near him and shoots it in the head several times. After which the dog creature falls to the side, whimpers/wheezes as Riddick watches (he is helpless because he has been hit several times with tranquilizers), and then it finally dies. Can’t even watch a damn alien movie anymore without them adding in a dog of sort to kill off. Shitheads.
There is a fairly graphic assault after some tense exchanges. The attacker successfully pins a woman and licks her face. This woman is the only woman in the movie, and it's worth noting that nearly every other character--including the ostensible hero--makes lewd comments towards her. This is probably one to skip if you're triggered by any sort of sexual violence.
A montage depicts Riddick developing a resistance to a venom through extreme measures: he's shown with an arm tied off, repeatedly injecting himself with a makeshift syringe. After the first injection, he vomits and collapses.
After he injects himself with the poison, Riddick gets sick. There is a bit of warning and it’s pretty quick. Time is about 27:15 in the Director’s Cut