During WWI, an injured and shell-shocked David Powlett-Jones applies to teach history at an English boys' public school, but he's concerned about whether a lower-class product of the Welsh mines can fit in.

On a holiday in Wales, David meets Beth, a vivacious young nurse from Swansea who literally sets her cap at him. After months of corresponding, David invites Beth to visit Bamfylde for the Founders' Day festivities.

David faces his wedding day with Howarth's gruff encouragement. Beth settles happily into life at Bamfylde, but David becomes agitated over a confrontation with Carter and a wealthy board member.

The twins arrive, and David gets an opportunity to shine as a substitute housemaster. Beautiful Julia Darbyshire takes a teaching post at Bamfylde, but she finds the atmosphere stifling and the isolation unbearable.

David takes over Havelock House for good and makes a curious choice for house captain. Everything goes well until Winterbourne, a Havelock boy, goes missing.

Stumbling about the moors, David finds a reason to return to Bamfylde and carry on. Five years later, sustained by his teaching and friendships with Herries and Howarth, he resumes his writing.

When Herries announces his retirement, Carter and David square off in the competition for the new headmaster's position. Julia's gentle persuasion helps David overcome his reticence to love again but she declares that she will never return to Bamfylde.

As Alcock takes charge and Herries bows out, the contrast between the two men is stark. The new headmaster proves to be interested in economy and sanitation above all else.

Outraged by Alcock's campaign to interrogate boys he suspects of ""unhealthy friendships"", David lashes out and Carter moves on. David becomes fascinated with Christine, a feisty upper-class socialist and politician who despises Bamfylde.

Alcock arranges a formal board hearing to air his grievances against David. Despite the risk, David continues to take time away to support Christine's political career. At the hearing, Alcock issues an ultimatum.

The masters bid farewell to Alcock in their own unique ways. David becomes the heir apparent to the headmastership, but Herries cautions David that the job won't be handed to him.

Preliminaries to World War II have started. To David's delight and amazement, Christine shows up at Bamfylde to enroll a new student. A trip home to Wales for a family death stirs David's emotions about his divided loyalties. The German threat looms over everything.

David revels in his new life as headmaster and husband, but Christine struggles to find her place at Bamfylde. Howarth makes a telling final request, and a letter reveals the imminent loss of another dear friend.