The Watch Kill Bill: Vol. 1 Onlinequestion on everybody's lips after episode 4 of The Last of Usis, "Who is Henry?"

We certainly hear the name a lot from Kansas City's revolutionary leader Kathleen (Melanie Lynskey), who has made hunting him down a priority. However, we don't actually meet Henry (Lamar Johnson) until the very last moments of the episode. That's when he and his brother Sam (Keivonn Woodard) hold Ellie (Bella Ramsey) and Joel (Pedro Pascal) at gunpoint. Other than that brief glimpse, Henry remains a mystery.

Even when discussing Henry in HBO's The Last of Us podcast, the show's co-creator Craig Mazin remained intentionally vague:

"There's somebody out there named Henry. We don't know who he is. We know that [Kathleen and her Hunters] are looking for him, we know that Henry has a brother named Sam. We don't know why they're important, we just know that Kathleen is ready to throw the entire revolutionary army out there to find them and bring them to some sort of justice."

While we may not have explicit information about who Henry is, the episode does throw us a few clues as to why Henry is so important to Kathleen. In her first scene, in which she interrogates the doctor who delivered her, Kathleen wonders whether she's standing in the same cell where her brother was beaten to death. Later, she mentions looking for FEDRA collaborators, likely Quarantine Zone residents who passed FEDRA information about revolutionary activity.

From this, it's highly likely that Henry was a FEDRA collaborator, who played a part in the capture and killing of Kathleen's brother. His motives are as of yet unclear. But given how Kathleen says Henry "won't let Sam starve," there's a chance his actions were meant to protect his own brother.

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All these possibilities mark serious deviations from the Henry of The Last of Us game.

In the game, Henry and Sam are survivors from Hartford traveling through Pittsburgh. They meet Ellie and Joel while on the run from Hunters, who are looking to kill them and take their supplies. The four team up and try to make it out of the city alive.

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Meanwhile, the show sets up Henry and Sam as longtime residents of the Kansas City QZ. Plus, they have a personal connection to Kathleen (herself a show-only character). Seeing as Henry, Sam, and Kathleen appear to be sticking around for at least another episode, we can trust that episode 5 will clarify Kathleen's vendetta against Henry.

Based on her deep-seated hatred towards him, you can bet that their confrontation will be explosive — and likely cause emotional damage.

Episode 5 of The Last of Us airs Friday, Feb. 10 at 9 p.m. ET on HBO and HBO Max. Following episodes will air Sundays at 9 p.m. ET on HBO and HBO Max.