Here's one that I'm particularly proud of.
The Star Trek Motion Picture Trilogy that comprises II, III and IV. These movies have great themes, character moments, adventure, and it comes complete with a prologue (TOS Season 1 episode "Space Seed") and epilogue (Star Trek VI: The Undiscovered Country).
It's one of those trilogies that were made when every film was made to be self-contained since when they made Star Trek III, they didn't know what the next story would be. When you watch Star Trek IV, everything that III set up pays off wonderfully in IV. The Bird of Prey was a perfect vehicle that complimented the story to IV that you would think was the reason why they included it, which it wasn't. It could land, cloak and maneuver in atmosphere the way the Enterprise couldn't.
I also like how M'Ress' species makes an appearance at the end.