GeekPlanetOnline’s resident telly addict, Gillian Coyle, likes to write about the box almost as much as she likes to watch it. From soap operas to space operas, if you need some thoughts on a television show she’s your woman…

There are many characteristics that can be used to identify geeks, but for many of us, the collecting gene is a defining one. As children we didn't just have toys, we collected them. Lots of us still do. One of the oddest things that geeks collect though, is actors.

We all have those early moments when we realise that we are not like other people. For me, several came while watching telly with the rest of my family. A familiar actor would come onscreen and I'd know his or her name, but no one else would. My mum used to marvel, “How do you remember all those names?” I am geek. I collect.

Okay, maybe it's only odd to non-geeks. After all, everyone knows who Tom Cruise or Brad Pitt is, and they only make two or three movies a year. Character actors are in more films, more TV shows and often put in better performances more consistently. Why shouldn't we know their names and celebrate their talent? It's just that their names aren't in massive letters at the start of the programme, or on the poster for the film. 

Film character actors tend to be better recognised than those working primarily in TV. The likes of William H Macy, John C Reilly and Steve Buscemi might not open a movie, but people interested in good films will find their ears pricking up when their names are mentioned.

It's in genre television though, that the cult of the character actor thrives strong and proud. In his brilliant show Moths Ate My Doctor Who Scarf, comedian Toby Hadoke discusses the special band of recurring actors in Doctor Who. Knowing who John Abineri was even, against all the odds, helped him impress a girl. Okay, she was the actor's niece, but still. That's geek gold is that.

In the past, these character actors pretty much stayed unknown. Names like Gary Cole, Jeffrey Combs and Billy Drago mean nothing to most people. People like David Ogden Stiers, Saul Rubinek and William Sadler have been mainstays of genre and mainstream television for years, but it's only relatively recently that they've been rewarded with regular roles.

But there is a new breed of character actors. Actors who are not only known to casting directors as hard workers who can be relied upon to put in a solid performance, not only known to small bands of geeks who scan credits and IMDb, but who have their own fanbases who will follow them from show to show.

Incredibly, most actors in this category have never been a series regular. They may play recurring characters, or even semi-regulars, but they've rarely if ever headlined a programme or film. Yet the news that they'll be appearing in this show, or have a small role in that film lights up the internet.

Although he's been appearing on television since the late eighties, Mark Pellegrino probably first came to the attention of actor collectors (at least those who aren't usually fans of police dramas) in the Showtime drama Dexter. As Rita's no-good ex-husband Paul Bennett, Pellegrino put in a chilling performance, managing to appear more menacing than a serial killer! Bennett died in season 2, but both he and the actor playing him made a big impression on audiences. Pellegrino returned to bit parts after that, but by this time he had become an actor to look out for, and his guest roles in genre shows like Knightrider and Chuck kept him on the radar.

Fast forward to 2009 and Pellegrino lands recurring roles in two of the biggest genre shows on television: Lost and Supernatural. In the starkly contrasting roles of Jacob, the embodiment of good in Lost, and as the vessel of Lucifer in Supernatural, he ably demonstrated his range and skills. For now though, it looks like the dark side has won through, as he has been cast as the Herrick-analogue, Bishop, in the upcoming US version of Being Human.

Callum Keith Rennie first skirted genre TV in the much-loved Due South. As the ersatz Ray Vecchio, Ray Kowalski, Rennie made a welcome addition to the show and introduced an interesting dynamic. Name a TV show, and Rennie has probably appeared in it, but it was as Leoben (Number Two), the Starbuck-obsessed Cylon in Battlestar Galactica that he made the biggest impact. He has since appeared in Flashforward and as a regular in Harper's Island/Globe, as well as guesting as Russian Mobster Vladimir Laitanan in the last season of 24. Although he is currently starring in US police drama Shattered, he hasn't given up his genre work. It was recently announced that Rennie will be appearing in the pilot episode of the new Syfy series Alphas.

The king of this group of actors is, without doubt, Mr Mark Sheppard. If you don't know who he is, well, you clearly don't own a television. Since he hit our screens as the amoral but charismatic Badger in Firefly, Sheppard has been in pretty much every genre show of note, and always makes his presence felt.

Romo Lampkin was one of the stand out characters of BSG, despite only appearing in a handful of episodes. Plus, he was about the only thing that made the interminable court case bearable. Manservant Neville was a fitting recurring villain in Middleman, managing to be moustache-twirling without seeming the slightest bit campy. He played another recurring villain in Medium, the serial killer Dr Walker, and his performance was coldly sinister. His performances in Bionic Woman, Dollhouse, Warehouse 13 and Chuck have been equally impressive, but for me Crowley in Supernatural has been his best role since Lampkin. Sheppard is pretty much a guarantee of satisfaction: even if you're not a particular fan of a show, it'll be worth watching if he's in it.

The next notch in his genre belt? What else but the televisual home of John Abineri, Michael Sheard and countless other unsung hims off the telly: Doctor Who. It's like some kind of circle closing. That's awesome.