A wealthy, fatherless British clan kidnaps bums and hippies and forces them to participate in an elaborate role-playing game in which they are the perfect family; those who refuse or attempt escape are ritualistically murdered.
Unfortunately the movie Mumsy, Nanny, Sonny & Girly is not yet available on HBO Max.
| Directing | Freddie Francis | Director |
| Production | Katherine Haber | Producer's Assistant |
| Writing | Brian Comport | Screenplay |
| Production | Ronald J. Kahn | Producer |
| Production | Peter J. Thompson | Associate Producer |
| Sound | Bernard Ebbinghouse | Original Music Composer |
| Editing | Tristam Cones | Editor |
| Production | Rose Tobias Shaw | Casting |
| Art | Maggie Pinhorn | Art Direction |
| Costume & Make-Up | Philip Leakey | Makeup Artist |
| Camera | David Muir | Director of Photography |
| Writing | Maisie Mosco | Writer |
| Costume & Make-Up | Dulcie Midwinter | Costume Design |
