This episode welcomes viewers to the deadly world of the most armed and dangerous gangsters, assassins and con artists of the animal kingdom. A gang of flesh-eating fish take down a river rat; a Bengal tiger shows just how to get the job done—alone; a red-back spider lures, then eats, her date; a femme fatale like no other, mama brown bear goes head-to-head with another bear to protect her young; and a pack of killer whales demonstrate how they live up to their name. Watch and discover how these animals and more earned their spots on World Deadliest: Nature's Most Wanted.