For starters, Phoenix and Witherspoon do their own singing. As Phoenix said at a press conference at the 2005 Toronto International Film Festival, which showcased the film, “If people want to hear Johnny Cash, they can get his records—he’s made a few.” Witherspoon revealed that there were six months of rehearsals, five hours a day. They took voice lessons and guitar lessons.

The input shows. When Phoenix revs up into his Cash singing mode he is surprisingly convincing. Witherspoon gets Carter’s country sound right, and also has Carter’s bouncy, appealing manner. The film is worth going to just to hear the pair sing.

But it is, of course, the story of their intertwined lives that keep thing rolling, as scripted by director James Mangold and Gill Dennis. There’s a lot to pack in. There’s the childhood trauma of Cash on the loss of a brother, the hostility on the part of Cash’s father stemming from the accident, the drugs, the struggle for success, infidelity---quite standard stuff in bio movies.

With respect to Carter, she’s busy warding off Cash in her feisty way, and yet there is the building attraction that eventually leads to her succumbing, and although his on-stage proposal in the middle of a show seems corny, it apparently really happened that way. Add more angst in the relationship and in connection with their turbulent lives, and you have an idea of all that must be covered. There might have been much more had the film run as a mini-series.