The film opens with a man driving a circus trailer down a silent road. He meets up with another man, John Gaveneau (Garret Dillahunt), and it is revealed that he is attempting to purchase a bengal tiger for the creation of a "Safari Ranch". Initially not believing the tiger looks dangerous or exciting enough, the seller tells him a gruesome story and claims that the tiger is evil. We then see his stepdaughter, Kelly (Briana Evigan), with her autistic brother, Tom (Charlie Tahan), whom she has taken to a special hospital in order for him to get the care he needs while she is at college. However, Kelly's check is rejected and when she phones her bank she is informed that John withdrew all the money and closed the account.
James Duthie, jeune homme sourd écossais, quitte à vélo son village de pêcheur en mai 1951 pour voyager jusqu'au cercle arctique. Par la suite il raconte son voyage de 3 mois dans le livre I Cycled into the Arctic Circle, qui a inspiré le film Dummy Jim. Proche du documentaire, ce dernier est constitué d'un montage d'archives, d'animations et de bribes de fictions.
James et John sont deux frères éloignés l'un de l'autre mais cela va très vite changer lorsqu'ils se réunissent pour satisfaire les dernières volontés de leur père.