Megan's poem puts us inside a single frightening moment: someone is being chased, and there is nowhere left to run. The speaker spots a hurried figure moving through the shadows, and eyes that seem to be watching from far off. From there, fear takes over. The body reacts first, with a shiver "to the core," and then the mind, which is "burning with thought" about the possibility of dying.
The setting is only hinted at, but the breaking twigs suggest a wood or similar wild place. Those twigs are the only company the speaker has, which makes the scene feel lonely as well as scary. Running into a dead end is the cruelest turn, and the speaker stops, yet the sound keeps going, "one by one," as if the pursuer is coming closer step by step.
The short, unpunctuated lines make the poem feel breathless and tense. It ends abruptly on "sudden darkness," leaving us unsure whether it means blackness, unconsciousness, or something worse.