johnjohn, how wonderful to see you back here! <grin> I've missed you!

I have no idea of what this movie is about, but I could go with Faldage's Rx, if Anna's hyphen is added: I could approve saying, "It was a two-week notice."

However, movie titles generally don't have any context, and so in this case I think we have to go with the obvious interpretation. Therefore, it should have the apostrophe, because the whole phrase (anybody recall the 'at high tide' addition onto our 'happy as a clam' discussion?) is: two weeks' worth of notice.