How can a node appear in different places? This is the kind of planning-stage question that I tie myself up in knots with...

A film site has main nav headings for Comedy, Fantasy, Kids etc. Each menu item displays a listing View of content type 'Film' tagged with the relevant taxonomy terms. 

For example, 'Harry Potter' film is tagged as Fantasy and Kids, and appears on both listing pages. 

If the user goes to the Fantasy section and clicks on 'Harry Potter' to view the full node, it needs to appear within the Fantasy section.

To achieve this, I am thinking of using another View to display the node content in the correct section (so the user never gets to the actual node). Or maybe I can do something with Panels. Or perhaps some kind of dynamic menu management?

I just have that familiar feeling that there has to be a cleaner way with Drupal?
You can do this pretty easily with views...just build a view with different page or block displays that filters nodes by the different tags (a.k.a. Taxonomy Terms). You can manually build a menu that provides links to the different pages that correspond to each tag.