Skate or Die (S19E21)

The murders of three homeless men appear to be the work of a serial killer. As Detectives Lupo (Jeremy Sisto) and Bernard (Anthony Anderson) investigate, they discover that one victim was wearing a distinctive pair of roller-skates that did not belong to him. Realizing that this could be a case of mistaken identity, they suspect the murders may have been committed by a copycat who knows the identity of the real serial killer. (iTunes)