From the start, "Little Red Cap" subverts the classic fairy tale alluded to by its title. More commonly known today as Little Red Riding Hood, this classic fairy tale of a girl hoodwinked and eaten by a wolf is best known as a children's story. However, Duffy's poem opens "At childhood's end," making clear from the get-go that her "Little Red Cap" is less interested in childish tales and more interested in what comes next.
Additionally, this line introduces the poem's first extended metaphor by portraying childhood as a physical place, which the speaker can leave behind just like she might walk out of a neighborhood. Contributing to this metaphor are the use of "end" (a common suffix for street names in England, akin to "Road" or "Avenue") and a list of familiar landmarks on the outskirts of town: "The houses petered out / into playing fields, the factory, allotments." Each of these landmarks, especially the factory, paint the picture of a worn-out industrial town, and the further away the speaker goes, the emptier the landscape becomes, until all that's left are an abandoned railroad track and a "hermit's caravan" in line 4, emphasizing the area's isolation.
Along the way, in lines 2-3, the speaker describes the neighborhood allotments, or garden plots, as "kept, like mistresses, by kneeling married men." This strange simile offers the poem's first hint at its interest in sexuality as a theme. By comparing two very unlike things—gardening and illicit love affairs—it gives readers a glimpse into the speaker's state of mind and her sexual curiosity as she exits her childhood. Last but not least, the use of asyndeton in these lines helps convey the sensation of moving further and further away, of more and more barriers appearing between the speaker's childhood and the "woods."
Finally, at the end of this long walk, "you came at last to the edge of the woods." This clear-cut boundary between childhood and the next stage of life symbolizes the cusp between childhood and adulthood. This line of the poem also contains the first of only two uses of the second-person: "you came at last to the edge of the woods." By using "you," the poem invites readers to imagine themselves in the speaker's shoes, walking out of our own childhoods up to the edge of the woods. The second-person also creates an effect of universality—"you" could be any one reader, or it could be all of us—suggesting that the journey out of childhood and into adulthood is a shared experience that everyone must face.