Martin Sproale is a mild-mannered assistant postmaster who lives with his mother, has dinner with his would-be fiancee once a week, and bicycles dutifully to work every morning. Martin has only one unconventional hobby: He is obsessed with the life of Ernest Hemingway, his brilliant and macho alter ego.
His hobby is confined to collecting memorabilia and reading every biography he can find, until an ambitious outsider, Nick Marshall, is appointed postmaster over his head. Slick and self-assured, Nick steals Martin's girlfriend and decides to modernize the friendly local office by firing dedicated but elderly employees and privatizing the business. Suddenly, gentle Martin is faced with a choice: meekly accept his defeat as he always has, or fight for what he believes in, as his hero would.
Aided by an American scholar writing a thesis about the women in Hemingway's life, Martin begins to explore his own passionate side. As the pair delves deeper and deeper into Hemingway's psyche and plots Martin's revenge, they learn that there is a man behind every mouse - and a little bit of Hemingway in all of us.