Sam and Dean are investigating a string of brutal murders where the male victims are left with their hands and feet cut off and a strange sigil carved in their chests.
It turns out that this is the work of a bloodthirsty tribe of inhuman Amazons, but unfortunately by the time the brothers have discovered this Dean has already had a one-night stand with one of the tribe (Sara Canning) and the demonic females have him in their sights.
The Slice Girls is a solid, straight-forward Supernatural story, with the requisite legwork before the kill, but complicated by the fact that one of the tribe is actually Dean's daughter (Alexia Fast) and when she comes to kill her father the scenario is a dark reflection of the issues Sam had with Amy back in The Girl Next Door.
It's not exactly a subtle parallel, but Eugenie Ross-Leming and Brad Buckner's script has enough going on that you can overlook this rather heavy-handed development.
The episode also features a great supporting performance from Harry Groener (aka The Mayor from Buffy The Vampire Slayer) as a college professor the Winchesters' enlist to help them in their research - a role previously filled by the late Bobby Singer.
Where several episodes this season have tried to recapture the magic of the early years of Supernatural with 'simple' monster hunt plots, The Slice Girls actually succeeds, yet still feels part of the current season by bringing to bear the emotional baggage the Winchesters' have accumulated on their seven-year journey.
Hopefully, this episode marks an upswing in quality in what has been a very patchy season to date.