Based on the popular science fiction novel series by James S.A. Corey, The Expanse is back for its final season. After it was canceled by SyFy at the end of its 3rd season, a fan campaign mixed with some famous fans such as Patton Oswalt, Wil Wheaton, and George R.R. Martin generated enough buzz for Amazon Prime to swoop in and pick it up for its final three seasons.

As the series gets ready for its curtain call, here is a refresher on who’s who in the cast.

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James Holden (Steven Strait)

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Image via Amazon

Holden became the captain of the Rocinante after his ice hauling ship, The Canterbury was destroyed. He was born on Earth and joined the UN Navy only to be dishonorably discharged. As with most heroes, he is reluctant at first but has shown throughout the series to step into the role the solar system needed him to be.

Steven Strait starred in films such as The Covenant and 10,000 BC. He is also a musician who has contributed songs to various film soundtracks.

Naomi Nagata (Dominique Tipper)

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Image via Amazon

Naomi is a Belter and a highly skilled engineer for the Rocinante. She rarely talks about her past, but we have recently learned that she has a child with Marco Inaros who she hasn’t seen since he was a baby. She disassociated with Marco after she realized his violent tendencies. She is currently involved with Holden and has formed a bond with Amos over their complicated history with violence.

Prior to The Expanse, Tipper had roles in the films Vampire Academy and MindGamers.

Amos Burton (Wes Chatham)

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Image via Amazon

As the mechanic of the Rocinante, Amos is an Earther from the Baltimore area. He can be a bit of a loose cannon and is almost giddy with excitement if violence erupts. His softer side is shown in Season 5 when he protects and rescues Clarissa Mao after the attack on Earth. Holden kept him at arm’s length at first but grows to trust him after witnessing Naomi’s friendship with him.

Wes Chatham has starred in the television show The Unit and the film In The Valley of Elah, but is probably best known as Castor in the films The Hunger Games: Mockingjay Part 1 & Part 2.

Chrisjen Avasarala (Shohreh Aghdashloo)

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Image via Amazon Prime Video

Avasarala is currently the Acting Secretary-General of the UN and often works with the crew of the Rocinante as her (unofficial) eyes and ears. She is a career politician and is known for making controversial moves that have cost her not only her political positions but her family as well. However, she is one of the most powerful people in the Universe and will be depending on Holden and his crew for aid in defeating Marco and the Outer Planets Alliance.

Shohreh Aghdashloo has been acting in film and television since the mid-1970s. She was nominated for an Academy Award in 2003 for The House of Sand and Fog and she won a Primetime Emmy in 2008 for her role in House of Saddam.

Roberta ‘Bobbie’ Draper (Frankie Adams)

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Image via Amazon

Gunnery Sergeant Bobbie Draper is a Martian who becomes a bodyguard for Avasarala after being the lone survivor of the battle on Ganymede Station. The Martian Congressional Republic charged her with treason, but she was able to expose the conspiracy surrounding Project Caliban resulting in her being cleared of all charges.

Known for her starring role in the New Zealand television series Shortland Street and the film One Thousand Ropes, Adams has been a series regular for The Expanse since Season 2.

Camina Drummer (Cara Gee)

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Image via Syfy

Drummer is a Belter who is the former captain of the Medina Station and was second in command to Fred Johnson on Tycho Station. She was instrumental in brokering the deal with the crew of the Rocinante during the raid on Thoth Station. She and Naomi are close friends. She is currently the captain of the Dewalt in the Sohiro territory with her polyamorous family.

Cara Gee is best known for her roles in the TV Show Strange Empire and the Web Series, Inhuman Condition.

Clarissa Mao (Nadine Nicole)

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Image via Syfy

Clarissa or “Peaches,” as she is affectionately called by Amos, is the daughter of Jules-Pierre Mao of Luna and the older sister of Julie Mao. She was undercover as Melba Alzbeta Koh when she was out for revenge on James Holden who had exposed her father’s illegal activities. She eventually winds up arrested and put in prison on Earth for her crimes. After being rescued by Amos, she too will be joining the crew of the Rocinante for the final season, whether Holden likes it or not.

With recurring roles on the TV shows, Dante’s Cove and The Young and the Restless, Nicole was bumped up from recurring to a series main role in Season 5 of The Expanse.

Marco Inaros (Keon Alexander)

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Image via Syfy

Marco is an Outer Planet extremist with great animosity towards the Inner Planets. His destruction of the Augustin Gamarra caused Naomi to leave him and baby Filip when she realized how extreme he was going to be for the cause. Marco has also been involved with the bombardment of Earth, the MCR Parliament bombing, the Free Navy Conflict, and the Tycho Station Coup. As far as we know, he is the main antagonist as we head into the final season.

Keon Alexander is best known for his roles in the FX show Tyrant and the YouTube original Impulse.

Carlos “Bull” De Baca (José Zúñiga)

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Image via Prime Video

Bull served under Colonel Fred Johnson on Tycho Station. From the looks of it, Bull will be replacing Alex Kamal (Cas Anvar) in the crew of the Rocinante for the final season.

José Zúñiga has been a character actor for the better part of the last three decades with roles in such shows as ER, The O.C., and How to Get Away with Murder, just to name a few.

Filip (Jasai Chase-Owens)

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Image via Syfy

Filip is Marco and Naomi’s teenage son. Raised by Marco to hate his mother, Naomi, Filip is constantly striving for his father’s approval. It’s hard to gauge what he’s thinking since he finally met his mother face to face, but thus far, we have only seen loyalty to Marco.

With only a few credits to his name, Filip is Jasai Chase Owen's first major television role.

Rosenfeld Guoliang (Kathleen Robertson)

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Kathleen Robertson, probably best known for her lead roles in Beverly Hills, 90210, Boss, and Murder in the First, is new to The Expanse this season. Her character Rosenfeld is a fierce believer in Belter independence and will be a big part of Marco Inaros’ crew.

Also recurring are Krista Bridges as Sandrine Kirino, Andrea Davis as Admiral Tesfaye, Samer Salem as Josep, Vanessa Smythe as Michio, Sandrine Holt as Oksana, and Anna Hopkins as Monica Stuart.

The first five seasons are all available on Amazon Prime. The sixth and final season of The Expanse premieres on December 10th.

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