Movies series, books, games, TV shows... The final chapter is like an emptiness in you, a little part  of you that dies, goes to the void. It's a natural law, and we can't help it.
Of course, Harry Potter or Lord of The Rings wouldn't keep on going forever (for as much as I would like...). 
Isn't there a saying: "All good things must come to an end"? Well, there you have it. 

Since I mentioned Harry Potter, there's a lot of people around the world that miss it enormously, especially the youngsters that grew up with it, like me and my generation.
Thank you, David Yates, for dividing the final movie in 2 parts; it helped us to mentalize that the end was nigh... 

In the games topic, there are fantastical series that get's you so into the world, the story and the character(s) that is just terrifying.
I can say that I was really sad and angry and just shocked with the ending of Mass Effect. It is, for me and for a great deal of people out there, one of the best trilogies ever made until today and everybody wanted more.
Waiting each time for years after the semi-end of each volume of the game, so much work, assimilation and emotions for it just to end. Even with the perfect ending, that gets your hopes up. *trying not to put spoilers here* 
Already bought the 1st tome of the book series, "Mass Effect: Ascension" to try to fill that little voidy hole in me.
Thankfully, there's still going on The Elder Scrolls, Dragon Age, I still have hope in Fallout, GTA, Assassin's Creed, Dead SpaceBatman Arkham... Patience is the key. 

Changing to books, there's a particular series that I adore, there's a movie of the 1st book that is not that bad (what can you do?... *sigh*), but they should either do a remake and continue with the series, that really follows the books, or do a TV series, because the story is immense and complex.
Well, it's the The Inheritance Cycle, written by Christopher Paolini, being the 1st volume Eragon
It is a fantastical and original story, with maps and languages, great characters, and each book gets bigger and bigger; the author planned to be a trilogy, but it was so immense that he had to write a 4th volume and turn it to a series, that he called a cycle.
Putting aside the fact that it ended (THE DESPAIR!), it is a shame and deserting the fact that they did not continue the cinema franchise.
Let's ignore the 1st one, shall we? Or do it again. AND CONTINUE!
So awesome!
Going on to TV series, there's one that I always mention when talking about this topic, that has a huge legion of fans, only has 1 season with 14 episodes and that was cancelled for various reasons checked online:
Low adverstising, low ratings, not enough viewers, the episodes were aired out of order, too expensive... All this by FOX, of course, that WE ALL HATE. Let's not forget Buffy the Vampire Slayer, that was much more popular and that continued instead of the best sci-fi show ever. The pride in America...
In Portugal, it was aired correctly, but I only saw it from the episode 7 or 8, I think. I really had no idea, neither my family. It was my cousin that talked about it, so we ordered the show and watched it and it's the best thing ever.
Yes, imaginary person, you are correct, 10 million euros for you! It's Firefly!
I won't even give any more details, if you want to watch it or you're just curious, check online, try to watch the pilot episode. Of course, if you are a wee bit interested in sci-fi. 
A masterpiece indeed.
No more sadness today. Ta ta!