name of this movie

i'm looking for a name of this movie, i cant remember what its about and i dont know whose init but... at one part a white guy dresses up as a black guy and a black dresses up as a white guy, because they need to go into hiding, another tiny bit is there are three kids in t as well (and one of them looks like alfalfa from the little rascals but its not him) need serious help

thanx

This suspence is terrible, i hope it lasts - Willy Wonka