We all know that feeling: you've spent a lot of time watching your favorite TV series, invested in your favorite characters, only to have the rug pulled out from underneath you when the network decides to abruptly cancel that show.

Usually, this happens after a cliffhanger episode, which leaves the entire series completely unresolved.

This leaves us tossing and turning in our beds at night, unable to sleep because we know we'll never have knowledge of that great question: what happens next?

There are some series that we think about years later and still want to see return to TV, or at least get a film resolving unanswered plot points.

Fortunately, sometimes we get what we want: fans successfully funded a Veronica Mars movie, we kept pressing until Fox agreed to give us more of The X-Files, NBC plans on rebooting Heroes, we saw Netflix pick up Arrested Development, witnessed Yahoo pick up Community and learned about Showtime bringing back Twin Peaks.

Even classic series Doctor Who returned to our TV sets, only to become more popular than ever.

But there are still some series that haven't made their return yet. And here are five we think are worthy of coming back to TV, or at least, an Internet streaming service.

Firefly

Okay, so this one is pretty obvious. Fox only gave us one season of this space drama created and written by Joss Whedon. The series follows the lives of a crew of misfits on the spaceship Serenity in the year 2517 and saw both critical and fan acclaim. But Fox didn't quite understand the love we held for this show and canceled it quickly.

Eventually, Firefly got a movie, Serenity, and not only was that movie utterly depressing (Wash!), but it still didn't fill the hole that Fox left when they yanked the series.

Hey, Fox, how about a series that takes place before the movie (so we can bring the entire cast back) with more adventures of that ragtag crew? That wouldn't be so bad, would it?

Carnivale

Back in the day, HBO had a bad habit of canceling shows without giving us any resolution as to how things turn out. That's exactly what happened with Carnivale, which ended its second season on a major cliffhanger.

Carnivale takes place during the Depression following a man with strange healing powers who joins a traveling carnival. Eventually, he begins having prophetic apocalyptic dreams and visions. In the second season, his path eventually crosses that of a preacher with similar visions, a man who gains the power to bend others to his will. Of course, there's a huge climax, with everything left hanging in the balance at the end of season two.

And then HBO canceled the series. If anything, we'd like the network to bring back Carnivale as a mini-series just to let us know how it all ends.

Deadwood

Here's another series HBO didn't do justice to, only giving it three seasons. This foul-mouthed Wild West drama was the signature "do not miss" event of the week while it aired, but still didn't make the cut after its third season. The show featured a large ensemble cast, including Ian McShane as Al Swearingen (a character no one can forget), as well as Timothy Olyphant, Jim Beaver, Molly Parker, Powers Booth and Keith Carradine.

And yet that dream cast and the wonderful characters they created couldn't save the show. There were once rumors that HBO considered making several movies to tie up loose ends left at the end of the third season, but those plans never came to fruition.

Pushing Daisies

Pushing Daisies was this clever Bryan Fuller helmed show that only got a single season because ABC just didn't understand how witty it really was. The show told us the story of a man named Ned, also known as the pie-maker, who has the ability to bring the dead back to life with his touch. Of course, magic comes with a price, so that means he can only bring back someone for one-minute (a second touch sends that person back to death permanently) or another dies in their place. 

This quirky series was one of those that perhaps suffered from the 2007-2008 Writers Guild strike. Fuller only wrote nine episodes of the original 22-episode season and eventually tweaked the ninth episode to serve as a season finale, with, as you guessed it, a cliffhanger. Although the show got picked up for a second season, its ratings tanked and ABC decided to call it a day. 

Dead Like Me

Fuller also created a dramedy series for Showtime called Dead Like Me, that told the story of a girl named George who died and came back to life as a reaper, tasked with helping the souls of the dead find their way to whatever lies next. Although Fuller left during season one citing "creative differences," the series had two seasons.

The second season's finale left a lot of unanswered questions, and although there was a direct-to-DVD movie released with the option of bringing the series back, it never returned.

We still want to know what happened to George, her family and the other reapers. And just who gave Rube the names he eventually put on those yellow post-it notes?

[Photo Credit: Fox]

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