You know how it goes, there's big hype around a new show, the Pilot is shown to a decent reception but during it's run it starts to falter and the network announces that they will not be renewing for another season despite the season finale leaving you on such a cliffhanger. Or you may get a few seasons out of it but they let it run too long and they just kill it off before answering the questions that remained.
So what show(s) were you a fan of that was cancelled leaving you disappointed?
One recent example I have is The Event. Don't know if anyone has seen that but I enjoyed it and the finale was just so unfair to leave us with. :(
[spoil]The aliens transport their planet which is dying close to earth and then a plan to conquer the earth and make it their new home become apparent.[/spoil]