FIVE YEARS AGO, director Chris Paine closed his 2006 documentary Who Killed the Electric Car? with heartrending footage of General Motors hacks grimly pulverizing the shit out of their firstā€”and pretty marvelousā€”attempt at a mass-produced electric car, the EV1.

It was ludicrous, and the bad press clearly managed to pierce GM's thick hide. And, so, fast forward five years, and guess who starsā€”gauzilyā€”in Revenge of the Electric Car, Paine's upbeat valentine to electric vehicles? Uh-huh. General Motors.

But don't let the cuddliness fool you.

Revenge, a character study focusing on the archetypes behind electric cars' revivification, not so subtly lays out the real reasons for Big Auto's turnabout: ego.

Not high gas prices. Not environmenta- lism. And certainly not sentimentality.

Toyota, with its Prius, was kicking GM's ass on its way to becoming the world's largest automotive conglomerate. And Elon Musk, the upstart genius behind Tesla Motors, was building his own sporty, popular roadsterā€”making GM look lumbering and out of touch. (Big Auto has never much tolerated upstarts, right, Preston Tucker?)

And that's why Bob Lutz, a Detroit dinosaur plying his trade for GM in the last days of a decades-long career (he's the father of the Explorer and was a champion of the Hummer), oozes the earnest zeal of a born-again sinner as he escorts Paine's crew behind enemy lines and talks up the shiny new Chevy Volt.

Paine also takes us through the drama of the 2008 recession, which nearly killed GM and Tesla. (That is, until the feds tossed each a cash lifeline.) But because we know how it all ends, Revenge starts to dragā€”and even the charisma of its iconoclastic characters can't help it along.

It doesn't pick up again until the final few minutes, when the real stars aren't the suits, but the cars themselves: a parade of them, from a shitload of companies. Heading to a gas-free future.