I saw this movie when it was first broadcast on Network Television when I was eight-years old and it still holds up over time.
The film doesn't waste anytime. The opening minutes show the exterior of an old house and we hear the whispering of someTHING that lives in it, saying that they'll soon be free. Then we're introduced to married couple Sally (Kim Darby) and Alex. She loves the idea of fixing up this old place, which she inherited from her grandmother, though he's not so enthusiastic. He's also up for a promotion at work and has little time or patience for his wife. So when she starts seeing things, especially at an important at home dinner they are hosting for his co-workers, he gets really pissed. But she really is seeing something, these foot tall creatures with monkey bodies and heads that look like rotten fruit. It begins when she unlocks the door in the house that leads to her grandfather's study. She likes it and wants the local handyman to fix the fireplace. It's all cemented up with bricks. He tells her he can't do that, that "some things are better left alone", and that he was the one who blocked it up. After he leaves she unscrews the latch that's bolted on the back ash trap, which is a huge mistake. It's at this point that she had freed THEM.
The night after the party she's taking a shower in her bathroom and they switch the light off with a coat hanger. One of the creatures grabs the husband's straight-razor and says that he wants to hurt her but the other one says no, they'll get her the next night. She turns on the light and they are gone. But she flicks off the switch and catches them coming out of the cupboards. When she goes back and opens it up, they are gone. It seems as if they come out of the darkness itself. Because she knows that her husband won't believe her she keeps this to herself, though she confides in him that she wants to move and that they should sell the place. He has to go out of town the next day so she tries to hang in there and arranges to stay over at a friend's. However, an interior decorator she has over is tripped by the little monsters and he falls to his death.
She's hysterical and the doctor gives her sleeping pills to take, which she won't. Yet they somehow make their way into her coffee and she gets really sleepy. Her friend is still over and soon her husband appears, finally convinced that something is going on. So he calls up that old handyman, who originally warned his wife about the fireplace, and goes over there to hear the full story. While he's gone, though, they cut the power to the house and lure the friend outside while they drag poor Sally to the fireplace....
What really makes this creepy is the music and the appearance of these demons. The effect was done using real men in costumes and making all the surrounding objects huge, like flower pot they peer out of or the the straight razor they are holding. It's utterly convincing. It also has a very un-Hollywood like ending. DON'T BE AFRAID OF THE DARK is down and out one of the best made-for-television horror film ever made (along with TRILOGY OF TERROR and GARGOYLES).