TheSmall House at Allingtonintroduces Trollope's most beloved heroine, the charming Lily Dale, to the Barsetshire scene. Lily is the niece of Squire Dale, an embittered old bachelor living in the main house on his property at Allington. He has loaned an adjacent small house rent-free to his widowed sister-in-law and her daughters, Lily and Bell. But the relations between the two houses are strained, affecting the romantic entanglements of the girls.

Lily has long been unsuccessfully wooed by John Eames, a junior clerk at the income tax office. The handsome and personable Adolphus Crosbie looks like an enticing alternative; but Adolphus has his eye on the rigid Lady Alexandrina de Courcy, whose family is in a position to further his career. Bell, meanwhile, must choose between the local doctor, James Crofts, and her wealthy cousin, Bernard.