The discreet advertisement in The Times, addressed "To Those who Appreciate Wistaria and Sunshine", offers a small medieval castle for rent, above a bay on the Italian Riviera. Four very different women - the dishevelled and downtrodden Mrs Wilkins, the sad, sweet-faced Mrs Arbuthnot, the formidable widow Mrs Fisher and the ravishing socialite Lady Caroline Dester - are drawn to the shores of the Mediterranean that April. As each, in turn, blossoms in the warmth of the Italian spring and finds their spirits stirring, quite unexpected changes occur.
