Marvel’s Thunderbolts*: Bucky’s Arm Is Now a Marvel Plot Hole

One of the more interesting talking points to come out of the Thunderbolts* teaser trailer is Bucky Barnes and his Vibranium arm. Instead of teaming back up with Sam Wilson in Captain America: Brave New World, Bucky finds himself stuck with the outcasts of the Marvel Cinematic Universe in Thunderbolts*. Bucky’s taking a blast from the past with the return of his long hair and his car-attacking weapon from Captain America: The Winter Soldier, but it’s his metal arm that’s got everyone talking. The trailer for Thunderbolts* shows Bucky pulling his Vibranium arm out of the dishwasher, which isn’t something you normally see every day. But the arm also raises an MCU plot hole.

Wakanda gifted Bucky Barnes a Vibranium replacement for the metal arm he lost in his battle with Iron Man in Civil War. After escaping their fight with Iron Man, Captain America and Winter Soldier fled to Wakanda, where Bucky was placed under sedation while Black Panther’s scientists worked to remove his Hydra brainwashing. Once Thanos started invading Earth, Winter Soldier was back in action and packing a Vibranium arm to defend the planet. He’s had the arm ever since then, but it has made another appearance in the MCU without Bucky, and that’s in the Guardians of the Galaxy Holiday Special.

How Bucky’s arm showed up in Guardians of the Galaxy Holiday Special

Guardians of the Galaxy Holiday Special helped bridge the gap between Avengers: Endgame and Guardians of the Galaxy: Vol 3, all while taking the Guardians on a holiday-filled adventure. At the end of the Disney+ streaming movie the Guardians exchange gifts, with Nebula delivering a special gift to Rocket Racoon. When Rocket opens the elongated box, he finds Bucky’s Vibranium arm inside.

Rocket’s obsession with Bucky’s arm dates back to Avengers: Infinity War, when Earth’s Mightiest Heroes are fighting Thanos’ Black Order army in Wakanda. When all hope appears to be lost, Thor emerges on the battlefield with his new ax Stormbreaker, along with Rocket and Groot. Once the fighting picks back up, the Winter Soldier and Rocket are shooting their guns side-by-side, with Winter Soldier at one point picking up Rocket and spinning in a circle. Once Bucky drops Rocket, the furry Guardian asks Bucky how much it would cost to turn over the Vibranium arm. Bucky storms off without answering, with Rocket muttering, “Oh, I’m gonna get that arm.” 

The Guardians of the Galaxy Holiday Special made that statement true, but it was never revealed how Nebula got the arm. Guardians director James Gunn gave some tongue-in-cheek responses to fans when they asked that same question, but she somehow got it and it also somehow wound back up with Bucky just in time for Thunderbolts*.

If we were to speculate, perhaps Nebula just borrowed Bucky’s arm, and Rocket Raccoon gave it back to Bucky once he was done admiring it. Or Wakanda had several arms made and Nebula just got her hands on one. Unfortunately, the real answer is probably closer to this being one of those unsolved mysteries/Easter eggs that will forever go unanswered in the MCU. It’s not that big a deal in the grand scheme of things, and it shouldn’t interrupt your viewing enjoyment of Thunderbolts*. But that doesn’t mean fans don’t have questions about the plot hole.

Thunderbolts* opens in theaters on May 2, 2025.