While not titled "Past Imperfect," this specific season and episode number features the crew meeting their own descendants from a divergent past.
The guide for primarily refers to the police procedural drama CSI: NY , which aired on April 25, 2007. CSI: NY: "Past Imperfect" (S3E21) [S3E21] Past Imperfect
Danny and Hawkes investigate the death of Scott Colson at Coney Island. They discover a woman dressed as a cowgirl who used an air gun to inject Scott with a lethal substance, eventually linking the crime to Scott's brother, Jesse. While not titled "Past Imperfect," this specific season
A woman named Emma is found in a dumpster with her head wrapped in packing tape and her eyelids removed. This M.O. matches Clay Dobson, a serial killer recently released on a technicality. While not titled "Past Imperfect