An insect Wesen rises up out of the ground in the park and attacks a man, stealing his clothes and effects before going out for fun. Naturally, Nick and Hank are called to investigate the dead naked guy.
After a little research, they discover that this Wesen is effectively immortal, only emerging from underground for one day every seven years before returning to his lair with a new meal to feed him. A new human meal.
Monroe eventually recognizes him as one of the original colonists who helped found Portland, and that the park in which he lives underground was donated land to ensure he always had a place to return to.
The Wesen picks up a woman at a local bar and lures her back to the park. It goes wrong for him when Team Grimm shows up and engages him. The fight is cut short, however, when the woman actually rips his head off -- she was Wesen, too, and none too thrilled at being targeted for his next meal.
Meanwhile, a ghostly Meisner continues to torment Renard in increasingly creative ways, to the point where Diana notices. Meisner, frustrated with the situation, contacts a man who he thinks can help.
The man has Renard step into a "spirit vacuum" booth (naked!), but something seems to go horribly wrong, and now Renard is left totally at the mercy of a less-than-friendly Meisner.