Jacek was one of the contingent of Flaming Fist soldiers accompanying Duke Ulder Ravengard and stayed at Waukeen's Rest when it was attack. During the subsequent battle, he was killed. His body is at the entrance to Waukeen's Rest, alongside Fist Recruit Ephren who mourns his loss and says a prayer. He cannot be communed with using Speak with Dead.
Later in Act Three in Highberry's Home, talking to Molly the Orphan reveals that she is waiting for Jacek, her father, and that they had come to Baldur's Gate but he had to leave soon after.
