The prophecy that was uncovered comes to pass when a dark force arrives in Portland with its eyes set on Diana. In an effort to protect her, Nick, along with Capt. Renard and Adalind, returns to the scene of his first investigation as a Grimm. Back at the Spice Shop, Monroe, Eve and Rosalee make a discovery that uncovers the origins of the mysterious stick. Meanwhile, Hank and Wu are called to a crime scene that is connected to the gang's greatest threat.

Nick faces off against his greatest foe yet as it seems no weapon can defeat him. At the Spice Shop, Monroe, Rosalee and Eve search for answers and stumble upon a rare potion that may help the fight. Elsewhere, Capt. Renard and Adalind try to keep Diana and baby Kelly safe as the threat has its eyes set on the children.