Resident Alien is an American science fiction comedy-drama television series created by Chris Sheridan, based on the comic book by Peter Hogan and Steve Parkhouse, that aired for four seasons from January 2021 to August 2025 on Syfy. It stars Alan Tudyk in the title role as an extraterrestrial who crash-lands on Earth with the intent to destroy the planet but develops a moral dilemma. In July 2025, it was confirmed that the fourth season would be its last.
Contents
Premise
After crash-landing on Earth in a small Colorado town, an extraterrestrial sent to wipe out humanity kills a vacationing physician and takes on his identity. He is asked to do an autopsy on the town's doctor, who has died in unknown circumstances, and eventually takes over for the doctor at the town's clinic. He wrestles with the moral dilemma of his secret mission, while also dealing with the mayor's young son, who can see his true alien appearance. He develops compassion for humanity and ends up defending them from other extraterrestrial threats.
Cast and characters
Main
Alan Tudyk as "Harry Vanderspeigle", the titular alien with an unpronounceable birth name who has crash-landed in Patience, Colorado, killed the real Dr. Harry Vanderspeigle, and assumed his identity. He has been sent to Earth to destroy the human race, believing that this would benefit the planet, but he begins to question the morality of his mission after involuntarily forming human emotions. He is fascinated by humans and has learned how to speak English, as well as how to masquerade as a medical examiner from watching reruns of Law & Order. Although he attempts to blend in with people, he consistently stands out because of his misunderstanding of social cues and awkward speech and behavior. As the series progresses, he learns more about human emotions, behavior, and interactions, often closing episodes with a narration about what he has learned. He possesses superhuman strength, durability, and agility as well as advanced intelligence, shapeshifting abilities, and the power to alter or remove human memories. In the second-season finale, Harry is implied to be millions of years old, as he recalls seeing live dinosaurs.
Tudyk also portrays the real Dr. Harry Vanderspeigle (seasons 1–2), a corrupt doctor and assassin involved with a crime syndicate who killed the previous town doctor, Sam Hodges
Stuntman Keith Arbuthnot portrayed the alien for the first season while in his true form: an androgynous humanoid Octopodiform-like being. For the second season onwards, Tudyk performed the alien scenes using a practical effects-created mask.
David Bianchi portrays Goliath (recurring season 2), Harry's future self, who traveled back in time and claimed a new human form as his own to save humanity from destruction. Goliath's artwork was created by Joe Vaux, storyboard artist and animation director for the TV show Family Guy.
Sara Tomko as Asta Twelvetrees, the assistant to the town doctor at the Patience health clinic and a member of the Ute Native nation. In high school, she had an abusive relationship with classmate Jimmy and placed their daughter Jay for adoption. She is the first person after Max to discover Harry's true identity.
Brylee Smith (guest season 1) and Zara Bacic (guest season 2) portray young Asta in flashbacks
Recurring
Ben Cotton as Jimmy (season 1; guest seasons 2, 4), Asta's abusive ex-husband and Jay's father
Kaylayla Raine as Jay, Asta's teenage daughter who works part-time at the Patience health clinic
Deborah Finkel as Abigail Hodges (seasons 1–2), the wife of Dr. Sam Hodges, the previous town doctor
Gary Farmer as Dan Twelvetrees, Asta's adoptive father and a Vietnam veteran, who owns the town's diner, Joe's Diner, which he has named in honor of a friend and fellow soldier he lost in the war
Mandell Maughan as Lisa Casper (seasons 1–2), a sociopathic government agent who works for General McCallister
Alex Barima as Lieutenant David Logan (seasons 1–3; guest season 4), an officer in the U.S. Air Force. After piecing together clues about Harry's crash landing, McCallister recruits him to find the alien and partners him with Agent Casper.
Jenna Lamia as Judy Cooper, Asta and D'arcy's childhood friend who works at the local bowling alley. She is sexually adventurous and often trades barbs with D'arcy.
Lilly Dean (guest season 2) and Gwenna Cooper (guest season 4) portray young Judy in flashbacks
Sarah Podemski as Kayla, Asta's cousin who is a mother and a lawyer
Acahkos Johnson (guest season 2) portrays young Kayla in flashbacks
Diana Bang as Ellen Cho, a nurse at the Patience health clinic who is disrespectful to almost everyone she encounters
Gracelyn Awad Rinke as Sahar Karimi, Max's adventurous classmate and close friend. She believes him regarding Harry's alien identity, and is the more mature and responsible of the two.
Guest
Jan Bos as Dr. Sam Hodges (seasons 1–2), the former town doctor for Patience, who is replaced by Harry
Michael Adamthwaite as Howard Wright, Eleanor McCallister's father, whose obsession to prove that aliens exist drove him insane. He only appears in flashbacks.
Giorgio A. Tsoukalos as himself (seasons 1–2), a ufologist who hosts a panel on Ancient Aliens at a UFO convention
David Lewis as Mitch Green (season 2), the mayor of Jessup
Alex Borstein as Carlyn (season 2), a laser physicist and Kate's cousin, who gets romantically involved with Harry
Tommy Pico as Drew (seasons 2–3), a member of Asta's extended family who lives in the city
Grace Dove as Sunny (seasons 2, 4), a member of Asta's extended family who is heavily pregnant
Lini Evans as Bethany Bloom (seasons 2–3), D'arcy's mother
Barclay Hope as Gerald Bloom (seasons 2–3), D'arcy's father
Taylor Blackwell as Liza Vanderspeigle (seasons 2–4), the estranged teenage daughter of the real Harry. In the third and fourth seasons, Harry's son Bridget uses her physical appearance as a disguise.
Maxim Roy as Violinda Darvell (season 2), the owner and operator of a prestigious art gallery in New York who was romantically involved with the artist "Goliath"
Robert Moloney as Tanner Corrington (season 2), a criminal associate of the real Harry
Episodes
Production
Development
Series creator Chris Sheridan stated that he was inspired to start the Resident Alien television project after reading the novels and comic book series of the same name. Upon being interviewed at a Television Critics Association panel in January 2020, he also stated that his real inspiration came from an aerial phenomenon "close encounter" he and his wife witnessed while honeymooning in the Bahamas twenty years ago.
On May 31, 2018, Syfy announced that the TV adaptation of Resident Alien was given a pilot order with Chris Sheridan as the show creator and Universal Cable Productions, Dark Horse Entertainment, and Amblin Television developing the pilot. On February 28, 2019, Syfy gave a series order with production starting in Vancouver, and David Dobkin directing and serving as an executive producer for the pilot. Robert Duncan McNeill executive produced and was producing director for the remaining episodes. On March 17, 2021, Syfy renewed the series for a second season, which premiered on January 26, 2022, and was split into two eight-episode parts; the second half premiered on August 10, 2022.
On July 21, 2022, Syfy renewed the series for a 12-episode third season. On November 15, 2022, Syfy reduced the number of episodes in the third season from 12 to 8. On June 18, 2024, it was announced that the series was renewed for a fourth season and would be simulcast on USA Network which premiered June 6, 2025. On July 24, 2025, Sheridan confirmed that the fourth season would be the final season of the series.
Casting
On September 20, 2018, Alan Tudyk was cast as the main character "Dr. Harry Vanderspeigle" in the pilot, along with Sara Tomko, Corey Reynolds, Alice Wetterlund, and Levi Fiehler. On January 31, 2020, Linda Hamilton, Mandell Maughan, and Alex Barima were cast in the recurring roles in the series. On February 12, 2020, Elizabeth Bowen was cast in the recurring role of Deputy Sheriff Liv Baker in the series.
Filming
Principal photography for the first season began on September 10, 2020, and concluded on October 14, 2020, in Delta, British Columbia, Canada. Filming for the second season began on August 3, 2021, and concluded on April 1, 2022. Filming for the first half of the second season took place in Ladysmith, British Columbia, with filming for the second half taking place from February 27, 2022. Filming for the third season began on January 30, 2023, and had concluded on May 2, 2023. Filming for the fourth season began on December 2, 2024 and concluded on March 31, 2025.
Release
On February 13, 2020, Syfy announced that the series would premiere in summer 2020. However, on October 9, 2020, the premiere was moved to January 2021, specifically January 27 in the United States. Internationally, the series premiered in Canada on CTV Sci-Fi Channel on January 27, 2021, and in the United Kingdom on Sky One the following day.
Reception
Critical response
For the first season, review aggregator Rotten Tomatoes reported an approval rating of 94% based on 31 critic reviews, with an average rating of 7.8/10. The website's critics consensus reads, "Resident Alien takes a minute to settle into its skin, but once it does it finds fresh humor in a familiar framework and proves a perfect showcase for Alan Tudyk's singular comedic skills". Metacritic gave the first season a weighted average score of 70 out of 100 based on 15 critic reviews, indicating "generally favorable reviews". For the second season, Rotten Tomatoes reported an approval rating of 100% based on 5 critic reviews, with an average rating of 7.7/10.
