1. Strip down for the Bonobos Undie Run, a two-mile fun run to benefit FCancer. It starts at the Humboldt Park Boathouse at noon, and registration costs $20.
2. The Driehaus Museum is hosting a murder mystery dinner party in its historic ballroom tonight at 7pm. Tickets are $175 for a three-course meal and cocktails.
3. See the Annoyance Theatre’s seasonal horror-comedy show, Splatter Theater, tonight at 10pm. Tickets are $20.
For more events, check in with Time Out throughout the day.