Cory Scott Allen

Mac joins forces with special agent Jack Dalton to recover a missing bioweapon and save hundreds of thousands of lives.

Lindsay worries Voight might be too close to a case to act objectively when a decapitated body is found in Lake Michigan.

Rayna seeks help from a different type of producer outside the country music world to try to give her a fresh sound.

When Maddie and Daphne learn about their parents' plans to divorce, Rayna turns to an old friend for support.

As Mac and the team investigate the suspicious death of Dawn's CIA supervisor, the evidence leads them to a corrupt CIA agent and a massive counterfeiting ring.