Avi Lake

The Intelligence Unit works to find the bombers. Even with government agencies in the mix, Voight (Jason Beghe) and his team work the case from their own angles and connections. Lindsay (Sophia Bush) and Antonio (Jon Seda) question doctors who handled the transplant surgery for an Ambassador from Syria, but no clues emerge. Olinsky (Elias Koteas) gets some solid intel and the team work from there. It’s a race against time as they realize there may be additional bombs targeted to detonate. Meanwhile Burgess (Marina Squerciati) sits vigil for her niece whose life hangs in the balance.

Lt. Casey (Jesse Spencer) and Dawson (Monica Raymund) volunteer to help at a charity run at Chicago Medical when a massive explosion sends Chicago into chaos. With one of their own missing in the blast, the firehouse is tested like never before.