The intruder paused on the staircase. For weeks he had come and gone in the big, old house, undetected by the widowed recluse who lived there - and an attic room had become his refuge from the drab realities of life. The old lady's isolation concerned Muriel Dean who added this cause to her other efforts to improve the human lot. While Muriel Dean meddles, a youth, another loner but one making an effort to conform, takes a girl to the cinema, embarking on a path that leads to murder - and to the snowbound house in which the old lady is cut off from all help during the long Christmas holiday..