Grimm season 5 episode 18
Reggie Lee as Sergeant Wu in Grimm season 5 episode 18 pictures NBC

Grimm season 5 returns with an all-new episode this Friday, as Nick Burkhardt and Hank Griffin investigate a new case of a dead man who has all his bones liquefied. Episode 18 titled Bad to the Bone will air this Friday (22 April) at 9pm EST on NBC.

The official synopsis reads as follows:

Click here to watch the episode online on NBC's website or click here to watch it via live stream in the US.

In the previous episode, Nick found out that Adalind is a hexenbiest again and that captain Renard is working for The Balck Claw, thanks to Eve. Meanwhile, sergeant Drew Wu, who is dealing with his bite, slowly starts showing signs of being a Lycanthrope, a Wesen that acts like a mythical werewolf.

The promo for the episode opens with a Wesen sucking up a man's insides, as the voice-over says: "This creature is bad to the bone. And it's about to devour one of their own." Hank and Nick arrive at the crime scene and Wu tells them: "I don't think there is a bone left in his body." The promo ends with the Wesen dragging Wu as Nick says: " I think it got Wu."

Actor Reggie Lee shared a TV Guide tweet that states something weird is going on with Wu in Grimm's upcoming episode. This confirms that episode 18 will focus on the police sergeant.

Will Wu's transform into a full werewolf? Is this the episode where Nick and Hank find out about Wu's secret? Watch this Friday's episode of Grimm season 5 to find out.