Becoming You (2020)

S1E15 Homecoming

When Claire reappears, having lost all memory of her time since boarding the ill-fated Oceanic flight 815, Jack and Locke devise a strategy to protect the group from her abductor, the enigmatic Ethan (guest-star William Mapother). He poses a deadly threat, vowing to eliminate the survivors one by one if Claire isn't returned. Simultaneously, Charlie grapples with his own feelings of inadequacy as Claire's lack of recognition deepens his regrets about a past relationship with a woman he had failed.