The year is 1975. Eight young boys aged 8-13 have been variously abandoned by their parents and are living in the long term care of Newham Social Services in East London. Elsewhere, Lady Rozelle Raynes and her husband Dick have had a new cruising yacht delivered to Walton-on-the-Naze in Essex.

Rozelle wonders what this means for her beloved Folkboat, Martha McGilda. She can’t bear to part with her and Martha makes it clear that she doesn’t want to go. She tears her mainsail, runs aground, knocks Dick over with her main boom.

Two worlds come together when Martha moves to the Royal Albert Dock and Rozelle commits herself to teach the boys sailing, seamanship and navigation every Tuesday afternoon. Some lifelong, life-changing friendships are about to unfold.

“I had often wondered what it would feel like to have the boat full of children spilling coke and crumbs all over the decks and swinging like monkeys from the boom,” wrote Rozelle. “And now I knew…”