How do i load swfs (as level 0 in AS2) in AS3

Can someone please help me figure out how to load .swf in a way that AS2 did it with levels . This was easy in AS2.
I have 15 movies whch are supposed to load on user click (simple Next button), and this was a no brainer in AS2 with level_0, but in AS3 im aware this works differently, and i cant find a simple solution in documentation.

any tip is greatly apreciated