Main

• Crystal Reed as Abigail "Abby" Arcane:
  A CDC doctor investigating a horrific life-threatening epidemic in her hometown while facing her past again.^[3] Melissa Collazo portrays teenage Abby.
• Virginia Madsen as Maria Sunderland:
  The wife of Avery Sunderland, whose grief over the loss of her daughter, Shawna, resurfaces when Abby returns home, and draws Maria into the supernatural mysteries of the swamp.^[4]
• Andy Bean as Alec Holland:
  A disgraced biologist working for Avery. Murdered when he starts to uncover an illegal operation in the swamp, his memories survive inside of Swamp Thing.^[5]
• Derek Mears as Swamp Thing:
  A plant-based entity created from the memories of Alec Holland. Possessing elemental control of vegetation and regenerative abilities, he attempts to defend the swamp, the town, and the natural world at large.^[5]
• Henderson Wade as Matt Cable:
  A police officer along with his mother, Lucilia, who finds himself in dire straits when supernatural events begin to threaten the town. He is also a childhood friend of Abby.^[6]
• Maria Sten as Liz Tremayne:
  A local newspaper reporter and bartender who is a close childhood friend of Abby Arcane.^[7]
• Jeryl Prescott as Nimue Inwudu / Xanadu:
  A blind fortune teller whose psychic abilities can reveal the future.^[8]
• Will Patton as Avery Sunderland:
  A prominent businessman in Marais, who, while publicly giving back to the community, is determined to harness the power of the swamp for profit as a pharmaceutical cornucopia. He was also the adoptive parent to Abby Arcane after her mother died.^[9]
• Jennifer Beals as Lucilia Cable:
  The "tough as nails and pragmatic" sheriff of Marais with a strong devotion to her son, Matt.^[10]
• Kevin Durand as Jason Woodrue:
  A biogeneticist, brought in to study the properties of the swamp, leading him to become fixated on unlocking its potential.^[11]

Recurring

• Leonardo Nam as Harlan Edwards: A CDC specialist who is Abby's second-in-command^[12]
• Elle Graham as Susie Coyle: A young girl who is diagnosed with "Green Flu", appears to have a mysterious connection to Swamp Thing, and befriends Abby
• Given Sharp as Shawna Sunderland: Abby's childhood friend and Maria and Avery's deceased daughter, who appears in both flashbacks and as a ghost to her mother Maria
• Ian Ziering as Daniel Cassidy / Blue Devil: A former stuntman who, after becoming semi-famous playing the demonic Blue Devil in a film, looks to regain his former fame^[13]
• Selena Anduze as Caroline Woodrue: A scientist and Jason Woodrue's wife who has Alzheimer's disease
• Macon Blair as Phantom Stranger
• Al Mitchell as Delroy Tremayne: Liz's father
• Michael Beach as Nathan Ellery

Guest

• RJ Cyler as Jones
• Tim Russ as Dr. Chowodury, a doctor at the Marais hospital
• Micah Fitzgerald as Munson / the Rot
• Adrienne Barbeau as Dr. Palomar, the assistant director of the CDC. Barbeau previously appeared in the 1982 film adaptation of Swamp Thing as Alice Cable, an amalgamation of Abby Arcane and Matt Cable.
• Jake Busey as Shaw

Development

In May 2018, DC Universe gave the production a script-to-series order. Mark Verheiden and Gary Dauberman were attached to write the first episode of the series and executive produce alongside James Wan and Michael Clear. Rob Hackett served as a co-producer. Production companies included Atomic Monster and Warner Bros. Television.^[2] Len Wiseman directed the series' first episode in addition to serving as an executive producer.^[15]

Despite being released on DC Universe, the series does not exist in the same fictional universe as the service's other live-action series, including Titans and Doom Patrol.^[16] On June 6, 2019, the series was canceled one week after its premiere aired.^[17]

Casting

In September 2018, Crystal Reed and Maria Sten were cast in the main roles of Abby Arcane and Liz Tremayne, respectively.^[3][7] Jennifer Beals was also cast in the recurring role of Sheriff Lucilia Cable, although she would later be revealed to be part of the main cast.^[10] More series regulars were later revealed, with Jeryl Prescott cast as Madame Xanadu,^[8] Virginia Madsen as Maria Sunderland,^[4] Will Patton as Avery Sunderland,^[9] Andy Bean as Alec Holland with Derek Mears as the Swamp Thing,^[5] Henderson Wade as Matt Cable,^[6] and Kevin Durand as Jason Woodrue.^[11] Ian Ziering joined the cast in the recurring role of Daniel Cassidy / Blue Devil,^[13] and Leonardo Nam was cast as Harlan Edwards in a recurring role.^[12]

Filming

Principal photography for the series commenced in early November 2018 in Wilmington, North Carolina, and wrapped on May 6, 2019.^[18][19]

Cancellation

In April 2019, production for the series was unexpectedly cut short due to creative differences with DC Universe's parent company WarnerMedia, thus reducing the original episode order from 13 to 10 episodes.^[20] Further reports stated that the series was canceled due to budget shortfalls after the expected level of tax rebates offered by the state of North Carolina were substantially reduced.^[21] A representative from DC Universe said that the streaming service was being re-evaluated and that there were no plans for a second season. The spokesman did not elaborate explicitly on why specifically the show was canceled.^[22]

Mears described the cancellation as a "heartbreaker" and felt the decision to cancel the show showed a "lack of respect" on DC's part. He added that members of the production had been told up until the cancellation "how amazing everything was... So it's a weird nebulous space that we're all in now because we don't know officially why that would happen, or why they canceled it".^[23] In mid-2019, a movement with the hashtag #SaveSwampThing began spreading on social media shortly after the series was cancelled in an attempt to save the series. Mears also showed his support of the movement.^[24] With The CW network acquiring the broadcast rights to the series, The CW president Mark Pedowitz did not rule out the possibility of renewing the series for a second season,^[25] but in January 2021, Pedowitz said it was unlikely the series would return on The CW and also commented that there was a slim possibility of Swamp Thing appearing on other Arrowverse series, such as Legends of Tomorrow.^[26]

Critical response

On Rotten Tomatoes, the series holds a 92% approval rating based on 39 reviews, with an average rating of 7.32/10. The website's critical consensus reads: "By leaning into the horror of it all, Swamp Thing swims deep into the trenches of this strange world and returns with a scary good TV show."^[33] Metacritic, which uses a weighted average, assigned the series a score of 69 out of 100 based on reviews from 6 critics, indicating "generally favorable reviews".^[34]

David Griffin, writing for IGN, said the series properly "honors the comic book origins" of Swamp Thing and praised the performance of Crystal Reed, Virginia Madsen, and Will Patton, as well as the film-making style of Wiseman. Griffin particularly praised the Swamp Thing's practical suit and found that any CGI used was not distracting.^[35] Daniel Fienberg of The Hollywood Reporter praised the creepy atmosphere and found the cast performances to be strong enough to carry episodes even when the monster was not on screen.^[36]

In a more mixed review, Kevin Yeoman, writing for Screen Rant, approved of the "nausea-inducing practical effects" reminiscent of John Carpenter's The Thing but criticized the writing and pacing and found the decision to not reveal Swamp Thing until the final moments of the pilot episode to be frustrating.^[37] Joel Keller of Decider found the horror elements made up for generic characters and an uninteresting mystery plot line.^[38]

Accolades

The series was nominated at the 2019 Saturn Awards for Best Streaming Superhero Television Series.^[39] Matthew Llewellyn as music editor on "The Anatomy Lesson" was nominated for the Outstanding Achievement in Sound Editing – Music Score and Musical for Episodic Short Form Broadcast Media award at the 2019 MPSE Golden Reel Awards.^[40]

Cancelled spin-off

Before the cancellation of the Swamp Thing series, there were plans to introduce Justice League Dark and create a spin-off series based on that team.^[41]

Arrowverse

Swamp Thing, as depicted in the series, makes a cameo appearance in the Arrowverse crossover event "Crisis on Infinite Earths" through archival footage of Mears as the character. The event depicts Swamp Thing as being set on the world of Earth-19.^[42]

Titans

Swamp Thing, as depicted in the series, makes a cameo appearance in the Titans episode "Dude, Where's My Gar?" via archival footage.^[43]