Watched all seven episodes of Seasons 1 and 2 of the U.S.A.'s 2021 Catching Killers

Season 1 is comprised of "Body Count: The Green River Killer," about trucker Gary Ridgway, who sexually abused and killed a total of 49 women, most of them prostitutes, including a 14-year-old runaway, beginning 1988 in Seattle, Washington; "Manhunt: Aileen Wuornos," a lesbian hooker who killed seven middle-aged men beginning 1990 in Marion County, Florida; "Truth Lies: The Happy Face Killer" (over two episodes), about three suspects who all own up to killing a woman yet contradict one another, in Portland, Oregon; "Bind, Torture, Kill," about serial killer BTK, Christ Lutheran Church president Dennis Rader, who massacred a family and killed women from 1974 - 1991 in Wichita City, Kansas; "The Phoenix Serial Shooter," about Samuel Dieteman and Dale Hausner, who participated in drive-by shootings in 2006 in Phoenix, Arizona; and "The Toronto Village Killer" (over two episodes) about real-life cannibal Bruce McArthur, who picked up, killed, and processed as meat men, mostly from the Gay Village, 2012 - 2017 in Toronto, Canada.    

The series focuses mostly on the valiant efforts of the police and detectives to identify, track down, and apprehend the perpetrators, and only secondarily on the victims and on the psychology of their killers. The viewer is given a preview of the evil that exists in the world, and how dangerous it is to be dealing with absolute strangers.

All episodes are exciting and satisfying, except perhaps the last two in Season 1 ("Truth Lies: The Happy Face Killer"; that an old woman would admit to committing a murder only to get her husband out of her life seemed extremely implausible to me.