Warning: This article contains spoilers for Captain America: Brave New World. Now that Giancarlo Esposito has slithered into the Marvel Cinematic Universe, the question is: Where will he strike next? The actor — known for his villainous roles in series like Breaking Bad, The Boys, and The Mandalorian — made his MCU debut on the big screen, playing a cold-blooded badass who tries to clip Captain America’s (Anthony Mackie) wings in Brave New World: Seth Voelker, a.k.a. Sidewinder of the snake-themed Serpent Society.
Videos by ComicBook.com
Esposito’s character was added during additional photography, replacing Diamondback (Rosa Salazar) and King Cobra (Seth Rollins) as the Serpent mercenary hired by Samuel Sterns/the Leader (Tim Blake Nelson) to steal adamantium and jeopardize U.S. President Ross’ (Harrison Ford) treaty with Japan.
RELATED: Captain America: Brave New World Leak Reveals Major Marvel Cameo Was Cut
Only Esposito’s Sidewinder and Jóhannes Haukur Jóhannesson’s Copperhead made the final cut, but Esposito isn’t expected to be a one-off villain. After a failed attempt on Cap’s life, Sidewinder is arrested, dishes expository intel on Sterns, and then warns Sam Wilson that he’ll inevitably escape prison.
When Esposito first teased his then-undisclosed Marvel role while making a convention appearance in May 2024, he told the crowd at Phoenix Fan Fusion, “It’s a role you won’t predict. It will be teased and there will be a series afterwards.”
Marvel’s TV slate includes Daredevil: Born Again (March 4), Ironheart (June 24), Wonder Man (December 2025), and Vision Quest (2026), so it’s a question of narrowing down the likeliest landing point for Esposito’s Sidewinder. While the character’s appearances have mostly been limited to a handful of Captain America comic books, he did appear — along with the Serpent Society’s Anaconda, Black Mamba, and Death Adder — as a member of the Assassins Guild in issues of Haden Blackman and Michael Del Mundo’s Elektra comic run in 2014.
But it’s Sidewinder’s link to adamantium that could tie him to Daredevil: Born Again, the upcoming series revival that is gritty, grounded, mature-rated and violent. Having been hired by the Leader to acquire adamantium — a metal alloy more indestructible than the vibranium in Wakanda with potential applications in technology, medicine, and defense that are “immeasurable,” according to President Ross — Sidewinder’s Serpents might have a role to play in the street-level corner of the MCU.
In the comics, the assassin Bullseye — an archenemy of Matt Murdock who once killed his lover, Elektra — had his spine shattered in the classic Daredevil #181. Issue #196 was the first to feature a mysterious masked figure known only as Lord Dark Wind, who paid off Wilson Fisk, the Kingpin, to bring the broken Bullseye to Japan so that his surgeons could reconstruct the assassin’s spine by lacing his bones with adamantium. (In return, Dark Wind wanted Bullseye to perform a political assassination in New York City.)
It was revealed that Dark Wind was Kenji Oyama, a Japanese scientist who was the first to develop the process to bond adamantium to human bone. As it happens, it was Oyama who was the surgeon who performed Benjamin “Dex” Poindexter’s (Wilson Bethel) spinal surgery in the third season of Daredevil. Although Dr. Oyama used the steel alloy Cogmium to reinforce and repair Dex’s spine, the discovery of adamantium might make the assassin even deadlier.
Will Esposito’s Sidewinder return in Daredevil: Born Again? Ironheart? Or elsewhere in the MCU? Tell us your thoughts and theories in the comments below.
