After the finale
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David was ready to leave this ungrateful town. After all he had done they were ready to lock him up. They would reap the benefits while David continued his work elsewhere, likely a country with no extradition treaty. But he wanted to see Marissa one last time. She was at this party at Adam's mansion, with Bianca. They were so happy together, David was glad for his daughter. But David saw something else, the glint of a gun. Someone was getting ready to murder his child. Without thinking David threw himself in front of her. The other guests had no time to process this before the gunshot. Some panicked, Ryan and Tad found JR in the secret passagway and tackled him to the ground until the police arrived. Bianca called 911 while Marissa stayed by her father's side. But David knew this wound was fatal, he'd seen it before. He gave Marissa a key and a note. She had to be told now, someone had to know the whole story.
: What's this?
Directions, and a way in. This is where you'll find the last Orpheus patient.
: Who is it?
Your sister. Babe.
After he told Marissa this David knew his work was done. He died in Marissa's arms.