In the series finale, the dagger that first killed Adam is rediscovered by a museum archivist who is then murdered, and the dagger taken. Working to prevent the detectives from discovering the existence of immortals, Henry determines that an antiquities specialist obtained the dagger in order to lure Adam, having learned of him from Mengele's journal. Henry's activities are noticed by Jo and Lucas, who both have heartfelt conversations with Henry about what he has meant to them. Adam draws Henry into a confrontation in the subway, shooting him with the 19th-century gun that first killed him; Adam intends that Jo, who has followed Henry, will either discover Henry's corpse or witness his disappearance. With the last of his strength, Henry injects Adam with a hypodermic needle. Henry then dies and disappears, to be reborn in the Hudson River within sight of Abe. Jo arrives after Henry is gone and finds his pocket watch. Meanwhile, the injection causes Adam to suffer an embolism, resulting in locked-in syndrome. Jo comes to the antiques store and reveals that she also found an old photograph of a timeless Henry, with which Adam had taunted him after finding it on Abigail's body. She demands an explanation, and Abe--who had previously advised Henry that he would need a confidante after Abe's death--urges him to "tell her." Henry offers to tell Jo "a long story.