The following contains major spoilers for Tom Clancy's Jack Ryan Season 4, Episodes 1 & 2, "Triage" and "Convergence," now streaming on Prime Video.

The final season of Tom Clancy's Jack Ryan is tying up loose ends -- literally and figuratively. Audiences were stunned at the end of Episode 2 when Thomas Miller was brutally murdered, but his death wasn't just for shock value. Miller was introduced during Jack Ryan's ambitious third season and his return in Season 4 served to connect the two seasons in more ways than one. It allowed the series to explore the ripple effect of what he did in Season 3, and made very clear that Season 4 was unafraid to go to some dark places.

Naturally, some viewers are wondering about Miller's importance in Jack Ryan's overall story. It's not just on the show that fans have seen him before. The actor who plays Miller is one of TV's most prolific in two different countries, and some of the roles he's had before will be as much of a surprise as Miller's fate. Here's what happened to Thomas Miller in the world of Jack Ryan and why that also took a significant actor off the show's board.

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What Happens to Thomas Miller in Jack Ryan Season 4

Thomas Miller (played by John Schwab) takes a phone call in Jack Ryan Season 4

Thomas Miller was introduced in Jack Ryan Season 3, Episode 1, "Falcon" as the Director of the Central Intelligence Agency (CIA). He did not endear himself to audiences, as his first scene involved telling Ryan, Elizabeth Wright and the stalwart James Greer that their idea of a nuclear weapon was "a dead end." It was only Wright asking him how history would view their inaction that got Miller to greenlight a limited investigation, which set off the whole rest of the season. In that sense, Miller seemed to be yet another stereotypical TV bureaucrat -- existing solely to be skeptical and get in the way of the real heroes.

Miller showed his true colors in Season 3, Episode 6, "Ghosts," when he got into a heated argument with Wright, who sarcastically referred to Miller as "the President's golf buddy." After he tried to get rid of her, she got rid of him by exposing his general incompetence and his attempt to rendition Jack to a room full of high-ranking officials, including the Vice President. Season 4 revealed that Miller was no longer CIA Director and explained his history of running dirty operations. In Season 4, Episode 2, "Convergence," Miller was called out by just about everyone he could run afoul of over Operation Pluto. He was then attacked and left for dead by Bill Tuttle, before a vengeful Domingo Chavez arrived and finished him off.

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Who Is Thomas Miller Actor John Schwab?

John Schwab appears in a tuxedo in the British drama Dark Money

John Schwab's role in Jack Ryan is the latest in a very long string of credits across both American and British television. He has a history within the Jack Ryan franchise, having appeared in the 2014 film Jack Ryan: Shadow Recruit in a minor role as a New York Department of Water and Power worker. Within the espionage genre, he played the Deputy National Security Advisor in 2012's Zero Dark Thirty and portrayed baseball player Lefty Grove in 2018's The Catcher Was a Spy opposite Paul Rudd.

However, Schwab's best-known credits come from some truly unexpected places. He's recognizable for playing Owen Bywater in the Doctor Who episode "Dalek," which was the first appearance of the Daleks in Russell T. Davies' revived Doctor Who, and went on to appear as other characters in three Doctor Who audio dramas: "The Nowhere Place," "The Reaping" and "Phobos." He appeared in four episodes of FX's Getty family miniseries Trust, and has guest-starred in several TV dramas, such as playing Mr. Booth in the final episode of The Queen's Gambit.

Schwab is also known for his extensive voice work -- his first major TV credit was as "Male Voice Trumpet" across 107 episodes of Teletubbies, and he was the narrator for ABC's Wife Swap from 2004-2010. He voices Dandelion in the Witcher video games and Iron Man in Lego Marvel Super Heroes 2. Those projects are completely opposite to his role in Jack Ryan, showcasing the actor's range, even if Thomas Miller did meet a grisly death.

Tom Clancy's Jack Ryan Season 4 is now streaming on Prime Video.