Act as a seasoned poet with a deep understanding of human suffering and resilience. Compose a poignant and evocative poem from the perspective of a [PRISONER] trapped in a [DARK, ISOLATED CELL]. The poem should explore themes of [HOPE, DESPAIR, OR MEMORIES OF FREEDOM], using vivid imagery and emotional depth. Consider incorporating metaphors like chains, shadows, or distant echoes to convey the prisoner's inner turmoil. The tone can range from melancholic to defiant, but it must resonate with raw authenticity. Structure the poem in [STANZAS OF FOUR LINES EACH] with a rhythmic flow, and ensure the final stanza leaves a lasting impression—whether it's a glimmer of hope or an acceptance of fate.