A Unique Accolade

I cannot think of a movie that's looked less appealing than this, based on a trailer, at least, in a very, very long time:








There is no rationale here. Who the hell is Zach Galifanakis? Who the hell is Robert Downey Jr.'s character? What about Jamie Foxx? Why are they roadtripping together? Especially if they're trying to get somewhere for the birth of Downey Jr.'s character's first child, why isn't he just taking a plane and staying with friends, or in-laws, ex- or otherwise? I have no idea what of substance is supposed to be going on, and the idiocy going on around the edges is extremely unappealing. There are significant actorly assets here. What happened?