After the Mirror Universe Jennifer Sisko kidnaps Jake Sisko, Captain Benjamin Sisko must travel to the Mirror Universe to retrieve his son. While there the Mirror Miles O'Brien wishes for Sisko to help him prepare their version of the Defiant for battle against the Klingon-Cardassian Alliance in what could mean freedom for the Terrans. By this time, the Terrans had taken Terok Nor (mirror DS9), and captured the Intendant (mirror Kira). They are preparing to defend against a recapture by the Alliance forces led by the Regent (mirror Worf). The Defiant turns the tables and forces abject retreat by the Regent. However, during the fight, mirror Kira kills mirror Jennifer, leaving Jake beside her body.