At first blush, one would think that the story of the Donner Party — a group of pioneers who encountered hardship and starvation on the trail to California, resulting in some of them resorting to cannibalism — would not be the sort of tale to inspire a musical. Trouble Puppet Theater Company’s new production, “American Blood Song: A Puppet Operetta of the Donner Party” (playing through Aug. 17 at the Vortex), shows that there is rich emotional and political resonance to be mined from the historical tragedy.

Written and directed by Connor Hopkins, “American Blood Song” follows the Donner Party from the start of their journey all the way through to its bitter end. This story is set to a score created and performed by Austin symphonic rock band Mother Falcon. In many ways, Mother Falcon is the heart of this production, using musical themes to keep the action moving, and delivering several powerful songs that effectively mix a folksy sound with the performative drama of musical theater.

In the first act, and toward the very end of the second act, Hopkins’ script is at its strongest, drawing parallels between the Manifest Destiny of the 1800s and the political and social problems of today’s America. In between, the story focuses tightly on the death, dismay and (post-mortem) dismemberment for which the Donner Party is known.

Because all of the characters are portrayed by puppets, Hopkins is able to get away with a grisly portrait of the carnage wrought by their various attempts to survive. Though there is frequently a tension between the more comedic elements of the puppetry and the grisly scenes that are taking place, the score helps to balance this out, as do the surprisingly grounded performances of the cast of actors/puppeteers.

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The cast — featuring both Trouble Puppet regulars and newcomers — are called upon to portray numerous characters in the party, and to imbue them with life and personality (even when they are sometimes only given one song in which to define themselves). Performers Marina DeYoe-Pedraza and Caroline Reck are particularly adept at this, bringing depth and nuance to several women in the party who see the destructiveness of patriarchal society embodied in their own group’s destruction.

The weak side of “American Blood Song,” though, is its focus on minutiae rather than on character. Multiple scenes of traveling west, followed by multiple scenes of slowly freezing to death, work quite nicely to create a sense of the monotony, tedium and encroaching doom that the party faced, but they also extend the play to a tedious length of its own, undercutting the political message of its conclusion. At the same time, the story frequently jumps around between different characters without ever clearly explaining the full details of what has happened, so that the individual scenes lack a coherent narrative whole, and the long running time thus feels unwarranted.

Even though it is plodding and confusing at times, the bright spots of “American Blood Song” are quite bright, indeed, and hidden within the overlong show is a powerful statement about America’s embrace of the ethos of “survival of the fittest.” I hope future iterations of this show will trim the fat a little in order to cut to the heart of that message, because it has many important things to say about the “blood song” that still defines our country.

(Tickets for "American Blood Song" are $15 to $35 at vortexrep.org.)