Natty Gann (played by Meredith Salenger) is a twelve year old Depression era girl whose single-parent father leaves her behind in Chicago while he goes to Washington State to look for work in the timber industry. Natty runs away from the guardian she was left with to follow Dad. She befriends and is befriended by a wolf that has been abused in dog fights, hops a freight train west, and is presumed dead when her wallet is found after the train crashes. Dad gets bitter and endangers himself in his new job. Meanwhile Natty has a series of adventures and mis- adventures in various farmhouses, police stations, hobo camps, reform schools, and boxcars.
八公（Forest 饰）是一条谜一样的犬，因为没有人知道它从哪里来。教授帕克（理查·基尔 Richard Gere 饰）在小镇的火车站拣到一只走失的小狗，冥冥中似乎注定小狗和帕克教授有着某种缘分，帕克一抱起这只小狗就再也放不下来，最终，帕克对小狗八公的疼爱感化了起初极力反对养狗的妻子卡特（琼·艾伦 Joan Allen 饰）。八公在帕克的呵护下慢慢长大，帕克上班时八公会一直把他送到车站，下班时八公也会早早便爬在车站等候，八公的忠诚让小镇的人家对它更加疼爱。有一天，八公在帕克要上班时表现异常，居然玩起了以往
