Meg, Jo, Beth and Amy have grown up together in Orchard House with their friend Laurie next door, and now it's time for them to go out and find their places in the big wide world, to do the great and marvellous things they've dreamed of and discover their 'castles in the air'. They each find themselves tested, and fall in love, but when tragedy strikes they find their best comfort is in each other, and home.
Jo and Professor Bhaer arrange a reunion for the March family and the original twelve boys of Plumfield. Ten years after the school at Plumfield was founded, there is now a college, built with a legacy from old Mr Lawrence. All Jo's original children are grown young men scattered around the world, and graceful young women with high ambitions. But young men face as many troubles as children do, and they are still "Jo's boys."