Every year, the quirky artists of Off Center Dance produce a fun, creepy and haunting Halloween show. At “Side Effects” you’ll see spine-tingling works by new artistic director Katie Ponozzo and company founder Kelli Brown performed in Boise’s newest collaborative space, Xanadu. Ponozzo recently took the reins of the company from Brown. “Side Effects” is a narrative, experimental performance that explores the world of Mary, a character who may or may not be crazy. It all depends on whether the zombies, ghouls and creepy dolls she sees are real. The performance is recommended for those 13 and older.