Ep 5. The Rat King

Nick and his gang delve into the world of rat creatures when the episode starts with a man, who happens to be carrying a mysterious green briefcase that has been marked with a rat-like emblem, being attacked by creatures with a rat-like appearance. Upon receiving information about the attack, Nick and Hank are led to an old sewer system where they discover a rat-like creature that has been dismembered and scattered all over.

Meanwhile, Monroe is struggling to control his urges as the horrid stench of the rat-body begins to take over his senses. He, however, manages to control his urges and leads Nick and Hank to find an underground world of rat-like creatures. They soon discover that all these rats are being controlled by a single entity, the Rat King.

As Nick and Hank delve deeper into the secrets of the Rat King and his army of creatures, they find out that the green briefcase carries more sinister secrets than they thought, and that it plays a significant role in the Rat King's plan. To make things worse, the gang recognizes one of their own in the Rat King's army, and their mission becomes more personal.

As always, Nick and Hank have to use all their wit and power to save the day, and this episode doesn't disappoint. The episode is packed with action, suspense, and drama, and the introduction of the Rat King adds another layer of mystique to the show.

The episode does an excellent job of exploring the relationships between the various characters, with Monroe struggling to keep his inner beast in check as the smell of the rat creature fills his nostrils. It also adds depth to Nick's character, showing how he continues to balance his life as a Grimm with his relationships with Juliette and the other people he cares about.

Overall, the episode is a must-watch for any fan of the show, delivering everything that we've come to know and love about Grimm, and introducing new elements to keep the show fresh and exciting. It's a well-written and well-executed episode that is sure to keep the audience on the edge of their seats.