“Ivy Gripped the Steps” is divided into three sections: The first and the third act as frames, being short and set in the present, 1944; the second, by far the longest section, contains a flashback to 1910-1912, when the middle-aged protagonist is between eight and ten years old. As the story opens, an external narrator describes the outside of a brick-and-stone house, which once was prominent but which has become abandoned and neglected since the war made Southstone, on the coast of England, part of the front line.

Ivy overwhelms the house, leaving a grotesque rather than a stately impression. Gavin Doddington, having a few days of vacation from the Ministry, has come to see the house where as a youth he visited his mother’s school friend, Mrs. Lilian Nicholson. During his last visit, which took place more than thirty years ago, he experienced a painful awakening regarding his relationship with Mrs. Nicholson.

In the second section, three visits by young Gavin to the prominent house at the seaside resort of Southstone are presented: the first in June, a second in January, and a third in September. As an eight-year-old boy coming to Southstone to shore up his health against the damp climate of his own inland home, Gavin is impressed with the luxury and ease at Mrs. Nicholson’s home. While at Southstone and under the care of the maid, Rockham, Gavin soon becomes enchanted with Mrs. Nicholson, whose life as a beautiful and charming widow of independent means seems constituted of social engagements and leisure. Her life contrasts with his own; his family struggles to make a living from the land. During his first visit, Gavin becomes aware of three important facts that he does not fully understand because of his youth: Mrs. Nicholson does not treat him like a child, he has become infatuated with her, and Admiral Concannon in conversation calls her “my dear.”

During his second visit, the intimacy between Gavin and Mrs. Nicholson grows, partially as a result of Rockham’s illness and partially because of Mrs. Nicholson’s manner. At a dinner party at the admiral’s and afterward in her conversation with Gavin, Mrs. Nicholson reveals her social nature to the reader but not to the young Gavin: She is generally self-centered and flirtatious. It is during the third visit to Southstone that Gavin experiences a painful awakening. He has been growing fonder of Mrs. Nicholson and has been treated kindly by her. He, however, overhears a conversation between Admiral Concannon and Mrs. Nicholson that makes him realize the true nature of the unlikely triangle made up of Mrs. Nicholson, Admiral Concannon, and himself. The admiral rebukes Mrs. Nicholson for being flirtatious with him and for mesmerizing Gavin. Mrs. Nicholson, not in control of this social situation, likens Gavin to a pet dog by way of excusing her behavior. When Gavin enters the room, Mrs. Nicholson attempts to retain her social veneer by speaking to Gavin as if nothing unpleasant has happened.

The last section of the story picks up chronologically after section 1: Gavin Doddington, who before the lengthy flashback has been staring at the abandoned house that once belonged to Mrs. Nicholson, notices that he has unconsciously picked a leaf of the ivy. Presumably, the flashback has been running through Doddington’s mind as he faced the house. He is surrounded by the devastation of war—an evacuated town, buildings intact yet left neglected, bombed sections of buildings, barbed wire, cement barriers—and the memory of the devastation of his feelings of love. It has only been with Mrs. Nicholson, before her veneer was shattered in that overheard conversation, that he has experienced such strong emotions. Gavin Doddington after his awakening is left with no feelings, “nobody to talk to”—“not a soul.” He in vain tries to pick up a young woman but is left alone amid the debris of war and emotional devastation.