Top Stasi agent Kleo Straub liquidates a target in a West German nightclub. Soon after, she must face a life-changing betrayal and a heartbreaking loss.

Determined to find her files, Kleo tracks down her former handler and makes her way into Stasi headquarters. Later, she seeks out Thilo in a dance club.

With Min and Uwe on her tail, Kleo bribes a little girl to deliver a poisoned Bundt cake to Mielke's jail cell. After a showdown, Kleo digs up a letter.

After Andi is wounded by Kleo, a double agent prevents him from unpacking the conspiracy behind the red suitcase. Sven, Kleo and Min move in on a mole.