If you haven't figured it out yet, I really like science fiction. One of my favorite shows is TORCHWOOD. It's a spin off of Dr Who. (TORCHWOOD is an anagram of Doctor Who.) It's on BBC America. They don't do seasons like we think of them. Every September there's a new season of NCIS starting. If BBC does do regular seasons, they don't do it with TORCHWOOD. Or Dr Who, but that's a whole different story.
TORCHWOOD is very well written science fiction. It's not just aliens and time travel. They do have that, but it's well written aliens and time travel. It's definitely a grown up show. You'll find sub plots that include a homosexual couple, an extra marital affair, and a man who never ages with a daughter & a grandson yet looks 26. And he's gorgeous too!
The mini series is available from On Demand. Scroll down till you find TORCHWOOD and start the series from the beginning. It's just 5 shows, and they're just over an hour each. All you really need to know to get started watching it is that Captain Jack can't be killed, aliens exist, Gwen's husband is very laid back, and Yento really does love Jack. Give the series a try, I think you'll enjoy it. Oh, and no, you don't have to watch Dr. Who to understand what's going on.