“Siren Song” is written in free verse. There is no formal pattern of meter or rhyme scheme. Free verse creates an informal, conversational tone. The effect is prose-like, but “Siren Song” remains poetic in its cadence and rhythm.

While meter plays no role in the structure of the poem, form does. The poem is composed of nine tercets—27 total lines. Atwood uses relatively short lines and simple, accessible language. Enjambment—the continuation of a thought past the end of the poetry line, with no end stop punctuation—builds tension throughout the lines and stanzas of the poem. Atwood specifically employs line breaks when and where she does to create surprise and multiple levels of meaning.

The first three stanzas introduce the siren song and seem fairly straightforward. However, the first three tercets comprise one long phrase that doesn’t see end stop punctuation until the ninth line. The first tercet announces the singularly irresistible song and ends in a colon to introduce the second tercet, which delivers the first bit of irony in a one-two-three punch. The song is a force.