Common Side Effects

The series follows Marshall Cuso and Frances Applewhite, two former high school friends who reconnect after Marshall discovers the Blue Angel Mushroom.

This mysterious mushroom appears to cure nearly any illness or injury, setting off a tense struggle involving a pharmaceutical giant, government operatives, and people with very different ideas about what its power should be used for.

The pilot episode premiered privately at the Annecy International Animation Film Festival in June 2024.

It was later screened publicly at Adult Swim's San Diego Comic-Con panel, before the full series debuted in 2025.

The show received strong critical praise and was renewed for a second season in March 2025.

Marshall Cuso discovers the Blue Angel Mushroom, a rare fungus with astonishing healing properties.

When he reconnects with Frances Applewhite, the two are pulled into a dangerous conspiracy centered on suppressing all knowledge of the mushroom.

The forces against them include Reutical Pharmaceuticals, one of the largest drug companies in the world, along with powerful government figures.

What starts as a scientific miracle quickly turns into a tense chase involving money, secrecy, ethics, and survival.

Common Side Effects blends adult animation with conspiracy thriller storytelling.

It mixes comedy, paranoia, corporate satire, and surreal psychedelic imagery in a way that feels both strange and surprisingly grounded.

Its visual style is distinctive, with exaggerated character proportions and expressive animation.

The show’s tone has often been compared to offbeat crime stories, especially works inspired by the Coen brothers.

Marshall Cuso

Marshall Cuso, voiced by Dave King, is the cautious and highly knowledgeable central figure of the story.

He is an expert in fungi, a former high school friend of Frances, and a man constantly forced to stay one step ahead of the DEA and other enemies.

Marshall has done charity work abroad and is deeply committed to understanding the Blue Angel Mushroom.

In the second season, young Marshall is set to be voiced by Elishia Perosa.

Frances Applewhite

Frances Applewhite, voiced by Emily Pendergast, is Marshall’s former lab partner and friend from high school.

She works as Rick Kruger’s assistant and is drawn into Marshall’s world while trying to help her mother, who has dementia.

Frances is initially skeptical about the mushroom, but she quickly realizes both its emotional and financial value.

In the second season, young Frances will be voiced by Mckenna Grace.

Agents Copano and Harrington

Agent Copano, voiced by Joseph Lee Anderson, and Agent Harrington, voiced by Martha Kelly, are DEA agents assigned to investigate Marshall.

They are best friends, understated in demeanor, and much more entertaining than a typical pair of federal investigators.

Copano is the more conspiracy-minded of the two, while Harrington is goofy but practical.

Rick Kruger

Rick Kruger, voiced by Mike Judge, is the incompetent chief executive of Reutical.

He constantly burdens Frances with trivial tasks and has a habit of playing farming simulator games in highly inappropriate situations.

Rick is both ridiculous and dangerous, making him one of the show’s most memorable figures.

Allies, rivals, and wild cards

Nick, voiced by Ben Feldman, is Frances’s often oblivious boyfriend who loves virtual reality gaming.

Jonas Backstein, voiced by Danny Huston, is a powerful Swiss financier and Reutical board member with major influence and a ruthless agenda.

Cecily, voiced by Sydney Poitier, is a deputy national security director who secretly works with Jonas and Reutical.

Hildy, voiced by Sue Rose, is Marshall’s eccentric mycologist mentor who becomes obsessed with possessing the Blue Angel for herself.

Sonia Applewhite, voiced by Lin Shaye, is Frances’s mother, whose dementia becomes one of the emotional drivers of the story.

Amelia, voiced by Shannon Woodward, is a laid-back mycologist hired by the DEA who is also caring for her sick son, Wyatt.

Kiki, voiced by Christine Ko, is a young Reutical researcher who understands the medical system and often argues the company’s point of view.

Zane, voiced by Alan Resnick, is Marshall’s half-brother, a self-trained herpetologist with a fascination for marine animals, psychedelics, and illegal animal imports.

Kenji is Copano and Harrington’s superior at the DEA.

Jimmer Jarvis, voiced by Mike Judge, is the sheriff of Averesboro, North Carolina, who becomes Marshall’s next-door neighbor and ally.

Rusty, voiced by Steve Hely, is Jimmer’s nephew, a gun-loving BMX-riding local with chaotic energy.

The series also features a range of supporting performers.

Shalita Grant voices Female DEA Agent, Susan, and Kelly.

Bob Stephenson voices Connor and Samurai.

Timothy Simons voices the DEA Dispatcher, a Lawyer, and Test Subject 3.

Andy Daly voices the Mysterious Passenger and Christopher.

Nicolas Cantu voices Tommy.

The pilot had its first private screening at Annecy in June 2024.

Its first public screening followed in July 2024 at San Diego Comic-Con.

The television premiere took place on Adult Swim on February 2, 2025.

The series later received an encore run on the Toonami programming block beginning March 2, 2025.

On March 28, 2025, Adult Swim officially renewed the series for a second season.

Season 1

Season 1 consists of 10 episodes, each running about 23 minutes.

The season gradually expands from a secretive medical mystery into a larger conflict involving corporate greed, law enforcement, black ops violence, and increasingly bizarre consequences of the mushroom’s use.

Episode 1: "Pilot"

Marshall confronts Reutical chief executive Rick Kruger and reunites with Frances Applewhite.

He reveals the Blue Angel Mushroom to Frances by using it to kill and revive a pigeon, while DEA agents begin closing in.

Episode 2: "Lakeshore Limited"

Connor, an employee connected to Reutical’s Peru operation, demonstrates the mushroom’s powers to Cecily and Jonas Backstein.

Marshall continues running from both the DEA and hired killers, while Frances investigates his destroyed home.

Episode 3: "Hildy"

Frances gives a Blue Angel Mushroom to her mother Sonia in hopes of curing her dementia.

Marshall visits his mentor Hildy, whose interest in the mushroom quickly turns dangerous after she experiences its strange effects.

Episode 4: "Dumpsite"

Frances learns that her mother has seemingly recovered.

She reunites with Marshall, who is trying to grow the mushrooms near a toxic waste site, only for violence to erupt around them.

Episode 5: "Star-Tel-Lite"

Marshall uses one of his last mushrooms to save a dying child.

Frances secretly records the miracle, and later she and Marshall discover a key clue to regrowing the Blue Angel.

Episode 6: "In the System"

Marshall is jailed and denied bail under suspicious circumstances.

Frances takes the mushrooms to Reutical, while a hitman arranges to be imprisoned with Marshall.

Episode 7: "Blowfish"

Marshall survives an assassination attempt in prison and is pressured into serving inmates as a kind of doctor.

At the same time, Frances suffers a devastating personal loss, and the wider conspiracy begins to come into sharper focus.

Episode 8: "Amelia & Wyatt"

Marshall revives after a staged death-like state and escapes with Amelia and her son Wyatt.

Frances breaks with her old life, Jonas faces his own health crisis, and rival groups converge on the secret of how to grow the mushroom.

Episode 9: "Cliff's Edge"

Marshall’s hidden farm begins producing Blue Angel Mushrooms, and sick people arrive as test subjects.

But misuse, side effects, and greed spiral out of control, ending in a brutal betrayal.

Episode 10: "Raid"

Marshall is revived once more as a raid hits the mushroom farm.

Frances and Marshall reconnect, new commercial schemes form around the mushroom’s byproducts, and several characters move into even more dangerous territory.

Joe Bennett and Steve Hely began developing Common Side Effects in 2019 under Bandera Entertainment, the studio founded by Mike Judge and Greg Daniels.

They wanted to combine a crime thriller structure with comedy, drawing inspiration from films such as Burn After Reading.

The creators also drew from real-world interests in medicine, ethnobotany, fungi, and psychedelic research.

Influences included Paul Stamets, Richard Evans Schultes, Terence McKenna, Wade Davis, and Albert Hofmann.

Marshall’s character was partly inspired by Paul Stamets and John Laroche, the eccentric orchid collector portrayed in Adaptation.

Another inspiration came from the story of R. Gordon Wasson, María Sabina, and the consequences of publicizing sacred mushroom knowledge.

Animation was produced by Green Street Pictures with an international team working across countries including France, Portugal, Spain, and Mexico.

Many artists involved had also worked on Scavengers Reign, another Green Street production co-created by Joe Bennett.

The series was made in collaboration with Le Cube, a partner studio in Argentina.

Its character design emphasizes unusual body proportions, helping the series stand out visually from more conventional adult animation.

The series score was composed by Nicolas Snyder.

Editing was handled by Tony Christopherson.

Executive producers include Joe Bennett, Steve Hely, Mike Judge, Greg Daniels, Dustin Davis, Dave King, James Merrill, Sean Buckelew, Benjy Brooke, Kelly Crews, and Suzanna Makkos.

The production team also includes Max Minor, Susan Shi, Paige Boudreaux, Jonathan Roig, and Jacey Bradley.

Adult Swim first announced the series in June 2023 at the Annecy International Animation Film Festival.

The pilot episode then premiered at Annecy in 2024 before its public debut at Comic-Con.

From there, the series rolled out as one of Adult Swim’s notable original animated shows of 2025.

Its release quickly built attention thanks to its unusual premise, strong voice cast, and mix of humor and tension.

Common Side Effects was met with critical acclaim.

Reviewers praised its inventive premise, expressive animation, dark humor, and unusual blend of science fiction, satire, and thriller storytelling.

On Rotten Tomatoes, the first season holds a 100 percent approval rating based on 26 critic reviews, with an average rating of 8.7 out of 10.

The site’s consensus described it as an addictive mix of expressive animation, heady concepts, and offbeat humor.

On Metacritic, the show received a score of 80 out of 100 based on six critics, indicating generally favorable reviews.

The series received a nomination for the Primetime Emmy Award for Outstanding Animated Program for the episode "Cliff's Edge" in 2025.

It was also nominated for the Television Critics Association Award for Outstanding New Program in 2025.

In 2026, it received a nomination for the Independent Spirit Award for Best New Scripted Series.

At the 53rd Annie Awards in 2026, the series won Best General Audience Animated Television Broadcast Production for "Pilot."

Vincent Tsui won an Annie Award for directing "Cliff's Edge."

Steve Hely and Joe Bennett won for writing "Pilot."

Tony Christopherson and Joie Lam won for editing "Raid."

Nicolas Snyder was also nominated for music for "Lakeshore Limited."

The series was produced by Green Street Pictures, Bandera Entertainment, Tell Me More, and Williams Street.

It airs on Adult Swim, the nighttime programming block of Cartoon Network.

The series has an official website and entries on major film and television databases including IMDb, Metacritic, and Rotten Tomatoes.