Synopsis
The action centres on the Dragon House. This was built by Master Balthazar Gellibrand late in Henry VII's reign. Some years later, a younger son, Nicholas, declared for Parliament in the Civil War and was disowned by his father. However, the family retained its property despite following the Royalist cause, because Nicholas had won Cromwell's favour. Nicholas was the direct ancestor of Jesanne, the heroine of the present-day story.
The story itself is set in the twentieth century. Sir Ambrose, present owner of the Dragon House, has lost sisters, son and grandchildren in various tragic circumstances during and after the Great War (1914-18), and is the last of his line.
He is obliged to trace the descendants of Nicholas the Roundhead, and summons fourteen-year-old Jesanne (an orphan and the only other surviving Gellibrand) from New Zealand to be brought up on the estate she will one day inherit. At first relations between the distant cousins are uneasy, but as Jesanne proves herself to be a true Gellibrand, a considerable affection develops between them.
Sir Ambrose tells Jesanne that she is now mistress of the Dragon House, and from the very start he treats her accordingly. She occupies the Dame's Suite and has her own personal maid. He teaches her the family traditions, including the Dragon House Ritual at Christmas, shows her the great Journall begun by her ancestor in 1531, and tells her of the mysterious Lost Staircase.
The house has stairs, of course, but they are not the original ones. This, and other matters of which Sir Ambrose tells Jesanne, belong to the private history of the family, and are part of the heir's training.
Sir Ambrose also makes arrangements for Jesanne's formal education. A governess, Miss Mercier, comes to live at the Dragon House. She and her pupil have some tussles over the curriculum, but at Christmas Jesanne acquires a companion in Lois Bennett, the niece of Sir Ambrose's agent. The two girls become friends, and later Lois shares Jesanne's lessons. Together they try to solve the puzzle of the lost staircase.
A closer inspection of the Journall reveals a clue to the mystery, but the actual discovery comes about through an accident in which Jesanne is concussed and fractures a wrist. She recovers quickly, however, and the story concludes with pleasant surprises for her and for Lois.