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...
Unfortunately the movie K-9 and Company: A Girl's Best Friend is not yet available on HBO Max.
| Writing | Terence Dudley | Writer |
| Directing | John Black | Director |
| Production | John Nathan-Turner | Producer |
| Editing | Michael Lomas | Editor |
| Sound | Dave Brinicombe | Sound |
| Art | Bob Cosford | Graphic Designer |
| Visual Effects | Nick Moore | Visual Effects |
| Costume & Make-Up | Ann Arnold | Costume Design |
| Costume & Make-Up | Susie Bancroft | Makeup Artist |
| Lighting | Barry Hill | Lighting Director |
| Camera | Michael Williams | Camera Operator |
| Production | Robert Gabriel | Production Manager |
| Sound | Peter Howell | Original Music Composer |
| Crew | Dick Mills | Special Sound Effects |
| Writing | Eric Saward | Script Editor |
| Visual Effects | Mat Irvine | Visual Effects Designer |
| Art | Nigel Jones | Production Design |
| Writing | Antony Root | Script Editor |
| Camera | Phil Wilson | Camera Operator |
| Sound | David Hughes | Sound |
| Production | Yvonne Collins | Production Assistant |
| Editing | John Burkill | Editor |
