Sarah Jane Smith arrives at the home of her Aunt Lavinia in the cozy village of Moreton Harwood, only to find that Lavinia is nowhere to be found and that the Doctor has left her a parting gift in K·9 Mark III. With the help of K·9 and Lavinia's young ward Brendan Richards, Sarah Jane starts investigating her aunt's disappearance. In the process, they discover that Moreton Harwood is home to a coven worshipping the pagan god Hecate and preparing for a human sacrifice...
Elisabeth Sladen
as Sarah Jane Smith
John Leeson
as K-9 (voice)
Bill Fraser
as Commander Bill Pollock
Ian Sears
as Brendan Richards
Colin Jeavons
as George Tracey
Sean Chapman
as Peter Tracey
Mary Wimbush
as Aunt Lavinia
Linda Polan
as Juno Baker
Gillian Martell
as Lilly Gregson
Neville Barber
as Howard Baker
John Quarmby
as Henry Tobias
Nigel Gregory
as Sergeant Vince Wilson
