4. Nathan Fillion: The unjustly canceled Firefly should have made Fillion a TV star. The unfortunately unsuccessful Serenity should have made him a movie star. And then, the incredibly underappreciated Slither should have made him a movie star, again. What is it about Nathan Fillion that he just can't seem to get a break? He has an undeniably likable charisma onscreen, which he can also turn on its head and suddenly become very creepy (as was the case when he played the murderous preacher Caleb on the final season of Buffy the Vampire Slayer). Plus, he seems like a genuinely decent guy, which might not seem like a big deal, but to me it counts for something. There's a lot of actors I like, there's not many I'd like to go grab a beer with. Fillion falls into that category. I guess I'm getting a little off topic about his acting abilities "“ just go rent all of the above titles I mentioned and see if you don't find yourself wondering how this guy isn't getting more leading roles.