All the Kind Strangers (1974)

A photojournalist sees a young boy walking along a back road with a heavy bag of groceries.  There's nothing for miles around, and concerned for the boy, he pulls over to speak with him.  The golden-haired moppet has apparently never heard of stranger danger, since he happily accepts a lift.

It's the adult who should be wary, however, for he's stumbled into a rather macabre situation.  It'll take him quite a while to twig to that.  While kindness prompts him to drive the boy home, he becomes increasingly exasperated as they head deeper and deeper into backwoods country.  When they eventually reach the house, he wants to move on straight away, but the boy cajoles him into coming inside.  There; he meets the other six children and the woman they call mother, though he knows from earlier conversation that their actual mother is dead.

When he goes to leave, he discovers that his car won't start, and he's forced to stay the night.  And it's only then that he discovers that the children are orphans, and the lengths to which they will go to secure replacement parents ...

So this is a pretty goofy premise, but the movie does a surprisingly convincing job with it.  The "kids" range in age from about six to sixteen or so, but there are seven of them, and that - coupled with the large, intimidating and well-trained dogs they keep - means that they can actually generate a sense of menace.

The film is also helped by a couple of strong performances.  The actors playing the kids are all refreshing non-annoying (they are creepy, but in a good way).  The adult actors meanwhile - Stacy Keach and Samantha Eggar - are rock solid.  Keach is good as the bluff photojournalist who for a long time can't quite come to grips with his situation.  Eggar meanwhile must portray a woman who has been held by the children for some time, and nicely conveys a sense of barely contained panic through her brittle veneer of cheerful domesticity.

A well made little film and a good demonstration of how to generate suspense and a sense of menace in a film without resorting to overt violence.