Best known for playing Agent Phil Coulson in SHIELD and the wider Marvel Cinematic Universe, the star will now play an as-yet-undisclosed role in the TNT series.
The broadcaster has also confirmed The Americans' Michael Aronov has signed on for Snowpiercer season 4.
The additions come as the show wrapped its third season last night (March 28) and, going forward, the series is set to change showrunners from Graeme Manson and Aubrey Nealon to SHIELD's own Paul Zbyszewski.
Speaking about their exit, the departing bosses said: "We have been blessed with an abundance of riches in building the world of Snowpiercer – from the incredible cast and crew, to the loyal fanbase and the building blocks afforded from the film and graphic novel.
"Tonight's finale is the culmination of several storylines, with unexpected twists and turns around every corner, and leading to an exciting fourth season with Paul's vision and creative storytelling continuing the incredible show momentum."
Zbyszewski added: "I'm so grateful to everyone at TNT and Tomorrow Studios for letting me join the riveting world of Snowpiercer that Graeme and Aubrey have so beautifully crafted and built.
"We have an exciting fourth season planned, and I can't wait to be on set with such an incredible cast and crew as we continue to explore new worlds, create new mysteries, and develop character relationships."
Snowpiercer, which stars Jennifer Connelly, Daveed Diggs, Mickey Sumner and Alison Wright, was given an early season 4 renewal last year ahead of the third season.
Snowpiercer airs on TNT in the US. UK viewers can catch up with each season on Netflix.