Mother of all endings

The year 2030 has always loomed large in the world of How I Met Your Mother.

It's the year in which, at the start of each episode, future Ted Mosby recounts tales of his younger years to his teenage children.

The comedy's ninth and final season recently ended in the US with fans, having been introduced to Cristin Milioti's titular mother across the season, finally learnt her name, how she met Ted and everything that happened up to 2030.

Australian fans are due to see the two-part finale next month, the culmination of years of laughter, pathos, catch-phrases and high- fives. It's a footnote to the final season set entirely over Barney and Robin's wedding weekend.

Josh Radnor, who plays the eternal optimist and romantic Ted, confessed he didn't want to know too much about his future wife and mother of Ted's children over the years, nor did he have any theories about who she would be and how they would meet.

"I had no thought about that, I mean I wanted her to be terrific because I thought he deserved it after all he'd been through," he said on the show's set in Los Angeles earlier this year.

"With the way I have to play Ted, forward, without knowing, it was better for me not to have that information. I wanted to play it honestly and he didn't know she's coming, so I didn't hassle them too much for information."

Learning how Ted met the mother of his children was the ultimate payoff for many fans but the highs and lows of Ted and his friends Lily (Alyson Hannigan), Marshall (Jason Segel), Barney (Neil Patrick Harris) and Robin (Cobie Smulders) is what kept them coming back every week.

"I think it was our hope that this would become a show that was about the audience wanting to spend time with the cast and hearing a life story about the lives of these unbelievably wonderful actors," said Craig Thomas, who created the show with Carter Bays.

"I don't think we were that scared about that. We always hoped we would have a long run, and we always knew how we wanted to end it. Of course there were voices that were impatient along the way, saying 'Why can't we just get to this?'

"But we always felt like we had the right timing up our sleeve when we reveal certain information, so we've grateful to everyone for sticking around. It's been a long ride, but it's been wonderful."

"Around season four people started to think our show was a big puzzle, like a game they were supposed to solve," Neil Patrick Harris added.

"So there were lots of trying to figure out what the 'Oh, the book is different on the back, the book was red on this side and now it's blue over here'. They were trying to solve the show, and it was never intended to be something to solve."

Jason Segel, who starred in the short-lived cult series Freaks and Geeks, feared the show would be cancelled early on.

"I had been part of a couple of shows that I loved being on and that I really liked and they got cancelled within the first season," he explained.

"So I really felt like there was no way you could equate quality with whether or not it lasted, so I was always ready for the show to be cancelled, and then the fact that we got along so well made it almost a sure thing to be cancelled.

"It's just the best gift ever that it stuck around for so long. We lucked out. It's been like a dream experience."

The actor and writer whose film career (Knocked Up, Get Him to the Greek, The Muppets) took off during HIMYM said the show mirrored what had happened in many of their lives.

"We watched each other go through, like, some really serious life stuff. People have got married and have children. That's a really special thing.

"As the characters evolved, all of our lives did as well, and some of it paralleled what we've kind of gone through as people. It's been like, this is the longest I've known any group of people besides my family."

For Harris, playing serial womaniser Barney gave him the chance to change people's perceptions, having made his name as the child star of Doogie Howser MD.

"I am really grateful for How I Met Your Mother's longevity given it's such a different character," he said. "I was a little wary I would continue to play all-American guys that have crazy friends.

"And instead I got to be the crazy friend for almost a decade."

'It's just the best gift ever that it stuck around for so long. We lucked out. It's been like a dream experience . . . we watched each other go through, like, some really serious life stuff. ' JASON SEGeL