I've just read Ian McEwan's 'The Cement Garden' some thirty years late. It was worth the wait.
I was completely convinced by the desultory teenagers, whose situation works as well today even though their setting is 'of the time'. The characters' increasing isolation, linking from their physical world to their psychological was apt. The intrusion of Derek, and the spreading crack, signalled inevitable outcomes. McEwan leaves us with the enigma of what happens, once the events are uncovered, thus keeping us engaged with the story long after we have closed the book.
A great read, but not for the feint hearted.