Whatever Became Of The Year 2000?

Spending a weekend at Lord Hawkcombe's country house, Brian Stead is offered the use of Hawkcombe's Hebridean island as a test site for a new Mogul rocket fuel. Peter Thornton visits the island and finds a hippie colony living there by informal arrangement with the bailiff, who are determined to fight for their home. Meanwhile Stead is much taken with Hawkcombe's sister, Lady Diana Embersham.