It's all fun and games until the hangover starts.
In this sneak peek from tonight's all-new Just Jillian episode, Jillian Michaels is feeling the pain following a wild night of partying in Chicago with hairstylist Chloe and two fitness instructors, and she only has a short amount of time to pull it together before teaching a workout class!
To make matters worse, her business partner Giancarlo Chersich returns from his vacation to catch the group in severe recovery mode!
"This is what happens when I'm not around?!" he asks after finding everyone in bad shape.
Check out the clip to see his full reaction!