The 1960s advertising series returns to U.S. television screens on Sunday after a 17 month-absence stemming from a contract dispute between Weiner and cable channel AMC.

That's a lifetime in an era of the 24-hour news cycle, and no-one is more aware of it than its creator Matthew Weiner, who told Reuters he decided to do a two-hour premiere because "I have been worried about it (the long gap) the whole time."

"I want people to see it already and I am excited that they seem to be excited," Weiner said in an interview, explaining the longer premiere "was a calculated desire to give the audience a bigger, better, super-sized dose of the show and get them into it right away. And also to say, 'I value you'."

But Weiner, who in 2010 left TV audiences with brilliant but mysterious ad executive Don Draper (Jon Hamm) suddenly proposing to his beautiful young secretary Megan Calvet (Jessica Pare), isn't prepared to say much about the upcoming Season 5. Not even what year it is set in.

All Weiner will reveal is that the new season will be very different, and that after the personal struggles that befell Draper when we last saw him, the enigmatic creative director is "in the next part of his life, good or bad."

"As it relates to the business and his personal life, Don is in a different place. That is the story I want to tell. You have to be prepared that this season is going to be about something different," he said.

Teasers, trailers and previews are not favored by Weiner, partly because he savors surprising fans of the show, but also because much of the fascination of "Mad Men" lies in the sub-text and in the slow-burning development of the show's myriad characters.

"The show has a lot of tension, and some of it is based on not knowing," Weiner said. "This is a commercial property whose success is tied to its mystery and there is very little entertainment out there that provides this surprise.

"Also I don't have giant nuclear bombs, and plane hijackings and bloodbaths. I have a story on a human level so that things that seem inconsequential like, 'When is it taking place?' and 'What is the state of Don's personal life?' - that is a lot of story."

Season 4 of "Mad Men" - which like its three previous seasons won the Emmy Award for best TV drama series - ended with Draper's out of the blue engagement, a promotion and a pregnancy for Joan Harris (Christina Hendricks), the loss of the ad agency's biggest account, and a drastic staff downsizing.

INVIGORATED AFTER LONG BREAK

Weiner predicted that after the second episode of Season 5, the audience "will be 'What happened?! Where is everything from last year?!'. And then by the third episode, they will start to see that this is a new story and they will hopefully get into it."

Far from being depressed by the protracted negotiations with AMC in 2010 that briefly threatened the survival of the show, Weiner said that he, the cast and crew went back to work invigorated, and with the assurance of three more seasons.

The return of "Mad Men" has been accompanied by a huge advertising campaign and promotions, ranging from a line of 1960s inspired clothing for retail chain Banana Republic to a retro edition of Newsweek magazine featuring ads with a 1960s look.

Despite drawing a regular U.S. audience of under four million viewers, the series has also sparked new interest in 1960s design and architecture since it first appeared in 2007.

It has also inspired a slew of 1960s TV shows, including the short-lived and controversial 2011 drama series "The Playboy Club", and "Pan Am", which is set around the dawn of the commercial jet age.

"I love this period and it was forgotten by America and I feel happy that I got to be part of something that reminded people of it," Weiner concluded about the renewed love affair with all things 60s.

But apart from its meticulous attention to detail, "Mad Men" is more than eye candy for nostalgia seekers.

"I was a little surprised at what people thought 'Mad Men' was, when I saw these other shows. They thought it was just a collection of clothing and style and that you could put it in any genre. That is not really what is unique about this show.

"Maybe 1963 has become a big part of our culture and our clothing and our interest right now," Weiner said. "But 'Mad Men' is moving on."

(Reporting By Jill Serjeant, Editing By Christine Kearney)

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