Reese Witherspoon hits the old, dusty trails on a journey of self-exploration in the first trailer for Jean-Marc Vallée's “Wild,” his first film since the Oscar-winning “Dallas Buyers Club”, TheWrap said.

Neither snow nor rain nor heat nor gloom of night stays Witherspoon's Cheryl Strayed, the real life writer who took a 1,100 mile solo hike on the Pacific Crest Trail after being afflicted by personal tragedies, including the death of her mother (played in flashbacks by Laura Dern).

A bad breakup also precipitates the extreme decision, though as she says, “breakup is a shorthand.” “The Newsroom” star Thomas Sadoski plays Cheryl's long-suffering first husband Mark, who stands by her through her many indiscretions including wild partying and infidelities … though even he has his limits.

Fox Searchlight releases “Wild” on Dec. 5, right in the heart of Oscar season.