Jon Snow and Daenerys Targaryen were not the only ones busy building an army during season six of “Game of Thrones.”

The fantasy drama has also amassed a legion of fans on Sky Atlantic and the channel’s boss believes it has now reached a “critical mass” in the UK.

Sky Atlantic director Zai Bennett told Business Insider there has been a “tipping point” in “Game Of Thrones'” popularity in Britain this year after the HBO series attracted record audiences and contributed to a spike in binge-viewing.

The entire series was watched by an average audience of 3.6 million on television, while viewing on Sky’s online services Sky Go and Now TV took this figure to nearer 5 million. This made it the biggest show in Sky Atlantic’s five-year history.

Of this, an average of 30,000 viewers stayed up until 2 a.m. UK time to watch each episode at the same time it went out on HBO in America. “I can only imagine they watched it in costume,” Bennett joked.

It was not just series six that proved popular with Sky’s 12 million subscribers. Box sets of previous series racked up 16 million streams on Now TV — a Netflix-style service that allows users to access Sky shows online for $9 a month — as UK viewers got up to speed with old episodes.

Bennett said Sky, which is 39% owned by Rupert Murdoch’s News Corp, experienced a surge in demand for Now TV ahead of “Game of Thrones” launch this year. He would not reveal specific figures, but said the show is a “massive business driver”.

He added: “It’s reaching a critical mass and people are just getting on with watching it. It’s reached a tipping point to be one of the cultural conversations to have. You do feel like you’re missing out if you don’t watch ‘Game Of Thrones’.”

Asked if “Game of Thrones” is at the peak of its powers, Bennett said he was “amazed” at how people are “willing to devour so much” and argued that further growth is possible.

HBO is planning another two seasons, but they will be shorter in length. There are usually 10 episodes in a “Game of Thrones” series, but the next two will only contain seven or eight instalments. Bennett said this will help keep the quality and interest high.

The Sky Atlantic boss is currently ploughing resource into homegrown dramas and said he has the “ambition and investment” to find a hit on the scale of “Game of Thrones.”

He has high hopes for “Tin Star,” a modern Western set in the Canadian Rockies and starring “Mad Men” actress Christina Hendricks. It is made by the 21st Century Fox-backed British producer Kudos.

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