When does Big Sky return?

The series premiered on ABC as a fall entry in the 2020–21 television season on November 17, 2020. In May 2021, the series was renewed for a second season which premiered on September 30, 2021.
"Private detectives Cassie Dewell and Cody Hoyt join forces with his estranged wife and ex-cop, Jenny Hoyt, to search for two sisters who have been kidnapped by a truck driver on a remote highway in Montana. When they discover that these are not the only girls who have disappeared in the area, they must race against the clock to stop the killer before another woman is taken."