Unsurprisingly, Joss Whedon has more than one entry on this list. Here's the first: his 2009 show, Dollhouse, which lasted for only two seasons rather than the hoped-for five. The action revolved around Echo (Eliza Dushku), an Active or "Doll" with temporary personality implants and skills. She gradually learns who she really is under all the personality wipes and what the company controlling the Dolls really wants. Thanks to two "Epitaph" episodes set in the future (one at the end of each series), fans discovered how things turned out. But much of the character development that was supposed to happen in the meantime had to be ditched in the rush to finish the story. And that's a shame because the fun of a television show is as much in the journey as in the destination. Like many series, Dollhouse got better as it went along. But as soon as it had found its feet, Fox cancelled the series.