At a funeral in Seattle, James Dickerson (Sean Six), calling himself "Ray Bell", approaches the mourning family and pretends to have known the deceased.
Speaking to clinical social worker Catherine Black (Megan Gallagher), Seattle police detective Bob Bletcher (Bill Smitrovich) reveals that the victim had been graphically mutilated during the murder.
Catherine's husband, profiler Frank Black (Lance Henriksen), is asked to consult on the case as a member of the Millennium Group.
Speaking to the family, Black finds that the victim's dead son has had a sports team badge taken from his body; he also realizes that the strange "Ray Bell" must be the killer.
Elsewhere, Black finds the name "Ray Bell" in the same newspaper as the victim's son's obituary, deducing that the killer may have been frequenting funerals before and had taken souvenirs from the deceased such as the badge.
Catherine identifies Dickerson as an archetypal "lost child", raised and neglected in foster care; he visits funerals to connect with society.
"Blood Relatives" is the first of two episodes of Millennium to be directed by James Charleston, who would return later in the first season to helm "Wide Open".
[6] Guest star Deanna Milligan, who portrayed the second victim Tina, would also appear in the third season episode "The Sound of Snow" in an unrelated role.
[13] "Blood Relatives" was first broadcast on the Fox Network on December 6, 1996;[14] and earned a Nielsen rating of 7.5, meaning that roughly 7.5 percent of all television-equipped households were tuned in to the episode.
Shearman and Pearson lauded Johannessen's "subtle writing", especially in the handling of the James Dickerson character; they felt the episode was "a study of a sociopath" which "humanises" its villain.
Club, Zack Handlen rated the episode a B, finding that its depiction of the character of James Dickerson added "some shades of gray" to the series' usual "black and white morality".
Handlen also felt that while the scene in which a woman is killed by a lake shore was "shocking without being exploitative", and was carried out in such a manner that "we don't feel as though she's targeted because she's a woman"; however, the climactic scene in which Dickerson's mother is attacked while stripping for a bath was seen as "a reminder of the show's inability to separate its lofty goals from its willingness to take the cheapest shots".