Arbok was a Wesen hit man in the TV series, Grimm. A Königschlange, an incredibly dangerous and unpleasant cobra-like creature who was Hired by a royal named Mia, to kill Monroe. He was the main villain of the episode, "Over My Dead Body."
He hired a Skalengeck to help him with the job. However, a female Blutbad named Angelina Lasser killed the Skalengeck who was supposed to kill Monroe, so Arbok and his assistant kidnapped her. Upon finding out that she was facing a Königschlange, this terrified Angelina, who knew that Königschlange were much more dangerous wesen. Coldly he molested her, while telling her, she was going to have to assassinate Monroe now, or he would kill her. What he didn't know, was Angelina was a old girlfriend of Monroe's, and so she betrayed Arbok, and went to Nick.
When Angelina delivered the seemingly dead body of Monroe, Arbok identified him as dead, unaware they were using a special potion, that brought him so close to death, that even Arbok's enhanced senses couldn't tell the difference. Thinking it was done, he called Mia in, to get paid. But as Monroe was quickly approaching real death, Angelina broke character and gave him the antidote. At that moment Nick and Hank attacked, confused Arbok ran, Nick ran after him. Recovering his senses, Arbok ambushed Nick, and the two thought, and Arbok's cobra like reflexes proved to be to much, even for Nick's Grimm powers. He Knocked him down and drew his gun ready to shoot him, when Hank caught up, and blasted Arbok with one blast from his shotgun, killing him instantly.