In “”Rango,”” the newest genre-bending adventure from “”Pirates of the Caribbean”” director Gore Verbinski, a pampered pet lizard goes on a Wild West quest to bring water to the tortured town of Dirt.

Whose idea was it to turn those latter-day Caribbean pirates Johnny Depp, Bill Nighy and (director) Gore Verbinski loose on a cartoon, ostensibly for kids? Because “Rango” requires some explanation.