A summer Sunday - sticky, windy and hot. Christmas is a week away. A family gathers at their holiday home by the sea and as the day begins, the grandfather waltzes through the garden, hand-in-hand with his grand-daughter. She's three years old, and she's enchanted. So is he.

''I've made a new friend,'' a delighted Harold Holt tells his family, assembled at Portsea for the holidays. ''This looks like a great Christmas.''

As Nicholas Holt remembers it, his daughter Sophie was inclined to shyness around her grandfather. He was the prime minister, after all, and typically came with an entourage in tow and business to attend to.

But not this Christmas. The PM had driven himself alone from Melbourne the evening prior, and this Sunday - December 17, 1967 - held promise of adventures far removed from matters of state. ''He never had any entourage at Christmas, a strange thing … the house had no fences around it or guards or security. The front doors were always left unlocked. We didn't let him remind us that he was prime minister, he complained that he was the odd job man around the house … he liked that. It was a very happy atmosphere.''