‘Common Side Effects’ season 2 teaser shows Marshall and Frances searching for answers

Adult Swim has released a new season 2 teaser for Common Side Effects, sending Marshall and Frances deeper into the mystery behind the Blue Angel mushroom.

The Blue Angel mystery gets stranger

Gizmodo's Justin Carter reports that the 45-second teaser finds the pair still on the run while continuing to develop Blue Angel. Their search for answers now turns toward the small white beings seen during mushroom experiences and an apparent culture around them that may stretch back centuries.

The footage also hints at volatile side effects, including angry outbursts and a dog's skin peeling. Gizmodo frames those moments as signs that Marshall's effort to go deeper into the beings' realm will put the people around him in greater danger.

Where season 2 picks up

The animated series follows former lab partners Marshall and Frances after Marshall discovers a mushroom that can heal almost anything, drawing pursuit from the DEA, pharmaceutical companies and international business interests. Bleeding Cool identifies Joe Bennett and Steve Hely as the creators, with Dave King and Emily Pendergast voicing Marshall and Frances.

Season 2 premieres Jan. 24, 2027, on Adult Swim and arrives on HBO Max the next day, according to Adult Swim's official teaser.