Guys, can anyone help?

I'm trying to get a series of movie clips to play on the main timeline of my flash project. I've read up about hierarchy but everything I seem to write in the actionscript doesn't work - I don't know what I'm doing wrong!

Basically I have the main timeline with my menu on, with buttons that are supposed to link to the movie clips on the same timeline, but it just isn't working. I have the instance names for the movies but the buttons can't seem to find them!

This is what I have so far:

on (release) {
targetpath("london");
gotoandPlay("1");
}

I hope this is making sense.

Cheers in advance,

Harry_028