"Harpua" is a Phish song that was a staple of their live concerts, but has now become a rarity and has only been performed live. Its first appearance on an album was on Colorado '88. Though it follows the same basic structure in every performance (see The Divided Sky and You Enjoy Myself for other examples of songs in which variation occurs within a fixed structure), Trey Anastasio narrates a different story at every concert.

The song's introduction is an a cappella "oom pah pah" melody sung by all members of the band.

A section of Gamehendge-related lyrics, concerning "me and Harpua", follows the a cappella introduction. They are occasionally improvised upon, but the melody remains the same. The Harpua section is composed in 7/8 time.

A new guitar lick follows the end of the "Harpua" section, introducing a unique story that Trey Anastasio tells at every performance of the song. Rarely, Jon Fishman interjects with humorous asides during the narration.

It is often (more clearly) revealed in this section that Harpua is a dog. Also, a character named Jimmy (through several performances it revealed that Jimmy is really Fishman i.e. 12/06/1996, 07/29/2003), who owns a cat called Poster Nutbag is always featured. Poster Nutbag will always be dead by the end of the story, often as a result of a disastrous occurrence (see below.) Other recurring themes included:

One way or another, Trey will kill off Poster Nutbag at or near the very end of the story using a natural disaster or some other form of death. This results in a conversation between Jimmy (narrated by Page McConnell) and his father (narrated by Mike Gordon) that is generally the same every time it is performed.

This request on Jimmy's part provokes the beginning of the next section, which is a new song in a poppish format.:

At this point there is a blues jam on the piano by Page McConnell. Then:

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