The villanelle is often a tortured poem, as tortured as some sestinas, because the pattern is so rigid and tight. Yet many poets have tried their hand at writing one because it is so challenging. The poem consists of five stanzas of tercets and a final quatrain stanza. Its meter is iambic pentameter. Here's the kick: line one MUST be repeated as line 3 of the second stanza, line 3 of the fourth stanza, and the second last line of the poem. In addition, line three of the poem MUST be repeated as line three of the third stanza, line three of the fifth stanza, and serve as the final line of the poem.

Do not go gentle into that good night,
Old age should burn and rave at close of day;
Rage, rage against the dying of the light.

Though wise men at their end know dark is right,
Because their words had forked no lightning they
Do not go gentle into that good night.

Good men, the last wave by, crying how bright
Their frail deeds might have danced in a green bay,
Rage, rage against the dying of the light.

Wild men who caught and sang the sun in flight,
And learn, too late, they grieved it on its way,
Do not go gentle into that good night.

Grave men, near death, who see with blinding sight
Blind eyes could blaze like meteors and be gay,
Rage, rage against the dying of the light.

And you, my father, there on the sad height,
Curse, bless, me now with your fierce tears, I pray.
Do not go gentle into that good night.
Rage, rage against the dying of the light.

This villanelle is quite brilliantly executed. Notice how Thomas changes the command of line one into part of a statment for stanza two. In this way he varies the motion of the line so it does not seem as if you are reading the same line over again. Can you see how he executes a similar transformation later in the poem? He wrote the poem, by the way, to encourage his father to fight off death.