Fallout Season 2 finally introduced Macaulay Culkin as a member of Caesar’s Legion in Episode 3, but a new theory suggests that his character might end up making a major change to the Wasteland as a result of Lucy (Ella Purnell) and the Ghoul (Walton Goggins) crossing paths with the bloodthirsty group.
Culkin’s involvement in the series was rumored back in November 2024, but Prime Video kept his role under wraps until fans got a glimpse of him wearing Roman armor in the trailer released in November 2025.
The third episode revealed that Caesar’s Legion is fractured into two halves after the death of the previous Caesar, who wrote a will that would reveal who he picked as his successor. As a result, the two groups are warring over his dead body, which remains in a No Man’s Land between the two camps.
Culkin plays a high-ranking of the Legion who holds the title of Lacerta Legate, but the show carefully chooses not to reveal his actual name. But the mystery surrounding the character has some fans theorizing that he’s about to become a major player.
Fallout fans think Macaulay Culkin’s character will unite Caesar’s Legion and start a new empire
Fallout fans think the Lacerta Legate will become the new Caesar in Season 2 because of the civil war between the Legion factions. When Culkin’s involvement in the series was first announced, his character was described as a “crazy genius” which means he could possibly be manipulating the conflict for his own benefit.
A Reddit theory suggests Culkin’s character will “end up taking control of the Legion and become a new Caesar. And then he’s going to launch his campaign to destroy NCR (now they were severely weakened) once and for all and then seize Hoover dam and New Vegas to build a stable unified empire.”
The theory included a blurry promo shot from the series which appears to show the Lacerta Legate wearing Caesar’s golden crown, implying that he’ll take over as the Legion’s next leader.
In Fallout: New Vegas, the companion Boone tells the player that the Legion has a whole line of succession planned in the case of Caesar’s death – so it’s also possible that Culkin’s Lacerta Legate is one of those people.
Including him as the chosen successor would be a good way of still leaning into the mythology established by the games, while forging its own path. Plus, a stronger version of the Legion could be a real threat to the remnants of the New California Republic, who have been weakened in the show thanks to Hank nuking Shady Sands.
Remember, Todd Howard said that Fallout Season 2 won’t retcon any of the New Vegas endings, and this would fit nicely inside the boundaries of the lore from the games. For now fans will just have to be patient until a future episode to find out the truth behind Culkin’s character.
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