The Missouri River is the gateway to the West: a thousand miles of mud, sudden torrents, treacherous currents, hidden snags, unexpected inlets, hostile Indians hidden behind every bend. And Captain Brant McRae knows every turn in it like the back of his hand. When his boat burns at its dock, strangers hire him to pilot the Western Star up the Big Muddy. McRae suspects there's something sinister about this job - but not that he carries a contraband cargo...