The Abbot revolves around the escape of Mary Queen of Scots from imprisonment in Loch Leven Castle and her flight to England following the battle of Langside. Her page, Roland Graeme, has been instructed to spy on her -- but his sense of honor, his loyalty to Mary (instilled by his Catholic grandmother, Madgalen Graeme) and his love for one of Mary Stuart's attendants, prevent him from betraying her. When it comes to it, in fact, he will aid her cause. . . .