Kids, if Bill Murray  gives you advice, you take it. In St. Vincent, Murray plays the title character who becomes the unlikely mentor to a young boy, Oliver (Jaeden Lieberher), when he moves next door with his recently divorced mom (Melissa McCarthy). It's a premise you've seen before, as Murray plays the grouch who dispels advice (how to beat up bullies, what to do in a strip club) while becoming friends with the kid. The difference here is that you probably haven't seen national treasure Murray do it, but that's not the only fun part of this trailer — Chris O'Dowd also plays a priest, while Naomi Watts  is an Eastern European stripper. St. Vincent comes out Oct. 21.