Nathan Fillion knows all about failure. Indeed, the 41-year-old Canadian is the first to admit that much of his early career as an actor was defined by it.
Yet when 'Weekend' meets up with the star in London to talk about his role in the comedy-drama series ' Castle', he gives the impression that he wouldn't have had it any other way.
"That's why I enjoy acting so much," he says. "There is always a threat of failure. You're putting yourself in front of a bunch of people saying, 'Watch me go'. And I'm crappy a lot. I make terrible choices a great deal of the time. They can't all be great," he says.
"But I like to say, 'Let me try something else, that was terrible'. Being okay with failure is alright. I simply have to do the best I can at what I'm responsible for."
For the early years of the Noughties, Fillion's screen career was defined by his involvement in the TV series 'Firefly', which aired for just 14 episodes in 2002, and which was later made into a moderately successful 2005 movie, 'Serenity'.
Beloved by a cult-like mob of fans and critics, the series -- the brainchild of 'Buffy' and 'The Avengers' creator Joss Whedon -- was dumped unceremoniously by the Fox network, making it one of those shows that would forever be included in, if not top, every 'Great Shows Cancelled Before Their Time' list.
"People are still connected to that show in a way that defies what I can believe," he says. "It follows me everywhere, even 10 years later.
"And it's not some nerdy guys in their mum's basement watching episodes over and over. They're high-powered lawyers and accountants, people who are well-to-do but passionate about these things."
Whedon has since had the last laugh -- the staggering success of 'The Avengers' has made him one of the most powerful directors in Hollywood -- but Fillion, in his own way, has too.
"Before Joss Whedon, nobody would look at me to play a leading role," Fillion explains. "Joss gave me that opportunity, and it changed my career. Our TV show was cancelled and it was heartbreaking, but he did everything he could, and he got us a movie out of it.
"After that, people considered me for leads in movies. Nobody has done more for me single-handedly than Joss."
Fillion is pleased about Whedon's success, too.
"The fact that he's enjoying success now -- success that he's always deserved -- is a great vindication," he says.
"I've always known that he's brilliant and tells great stories. I've always known he can touch an audience.
"Now everyone knows, and now I think it's his time," he adds.
In the years that followed 'Firefly', Fillion landed roles in movies such as 'Waitress' and 'Slither', as well as scoring a recurring role in ' Desperate Housewives'.
But having started out in TV in the US soap opera 'One Life To Live' and the 1990s sitcom 'Two Guys and a Girl' (opposite a then unknown Ryan Reynolds), it seems fitting that Fillion has found his greatest -- certainly his most consistent -- success on the small screen.
In 'Castle', Fillion plays Richard Castle, a bestselling mystery novelist who teams up with an NYPD detective, Kate Beckett ( Stana Katic), to crack a series of unusual crimes in New York.
While it may seem to some as if the show is mere 'schedule filler', 'Castle' is a solid show that has a big following in the US, to the tune of 12 million viewers a week.
"Any year that I'm on a television programme that doesn't get cancelled, or have the threat of being cancelled, I call a success," he laughs.
"When I did 'Two Guys and a Girl', every day we'd be like, 'Are we going to get cancelled? Look at the numbers!' It was a good lesson to me in how I could only worry about things that are in my control."
Fortunately, those worries are yet to set in for his current role.
"On 'Castle', there was never a threat of cancellation. People were always very happy with the numbers. They get happier with every year," he says.
"When you're on stage, if you do something right you get the immediate response as applause or laughter. When you do a television programme, you don't get that as much. This is a nice feeling."
He puts the show's success down to simply having "an element that makes it easy to like". "It's not a heavy-hitting, brooding weight put on the audience," Fillion continues.
"I love feeling something when I watch a TV programme, but 'Castle' has something a little different. It's light-hearted and doesn't take itself very seriously."
One of the other central appeals of the show is the 'Moonlighting'-esque 'will they/won't they/should they?' dynamic between his character and Katic's Beckett.
"When fans talk to me, it's always about the relationships and the chemistry, and the failure of them to get together," he says.
"My theory is that none of us ever want to think of ourselves as being flawed or stupid, but it sure is easy to watch people on TV and go, 'I know better than them. I know what's good for you'. It's very easy to watch someone else fail, and it's something we can all relate to."
The show is about to go into its fifth series in the US, but Fillion, conscious as ever about failure and the knocks an actor endures in this business, isn't growing complacent.
He says he's acutely conscious of his character evolving enough to keep the audience engaged and invested.
"I think Castle has done some growing up over the years," he says. "There are some things about him that may never change, which I think is fine. But it doesn't get boring. He's very playful, and not the nicest guy in the world. He's a little inconsiderate, which is fun to play."
He pauses for a moment, before continuing. "Making a TV show is a huge team effort. Everyone there is working really hard. I just happen to be one of the faces you see.
"It's hard to ever get lazy or complacent when there are 50 people waiting on you to do your bit so they can continue doing their bit."
'Castle' is on Alibi on Wednesdays at 5pm/9pm/11pm