It's A Sin: Channel 4 series gives All 4 record-breaking month

It's A Sin follows a group of friends during the 1980s Aids crisis

It's A Sin, Russell T Davies's hit TV drama, has helped Channel 4's streaming service to a record-breaking month.

The series has so far had 6.5 million views on All 4 across its five episodes, according to the broadcaster.

The complete box set only dropped on 22 January but that was enough to cement the platform's highest monthly figure since predecessor 4oD began in 2006.

Monthly figures are not regularly published by All 4 so the previous record is unknown.

But making the entire series immediately available to stream on All 4 has evidently paid dividends for the network.

Ian Katz, Channel 4's chief content officer, said: "The extraordinary performance of It's a Sin is a reminder that powerful drama with something important to say about the world can also be commercially successful."

It's A Sin follows a group of friends during the 1980s Aids crisis and stars Olly Alexander from pop group Years & Years.

What do the viewing figures mean?

Musician and actor Olly Alexander plays one of the leads, Ritchie, in the series

The 6.5 million figure relates to the total number of views so far across five episodes and is not a reflection of how many individual viewers the series has attracted.

For example, if one person watched all five episodes on All 4, that would count as five separate views.

The show's launch episode on its own attracted 3.26 million viewers, according to data from industry body Barb.

That is a consolidated seven-day figure and includes viewers who watched it live on its initial broadcast and those who watched on catch-up within a week.

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The numbers hold up well against other popular Channel 4 shows including Gogglebox, which regularly attracts a consolidated audience of more than five million viewers.

But The Great British Bake Off is still Channel 4's biggest hit, with the finale of the last series attracting a consolidated audience of 11.5 million.

Why did the series take so long to get made?

Keeley Hawes appears as Ritchie's mother

Given the success of It's A Sin, many may be surprised to learn that the series nearly wasn't made at all.

In an interview with Pink News, Davies said his script was turned down by ITV, the BBC and even Channel 4 first time around.

He described it as a "hard sell" due to it's subject.

"It's about people dying. It's a tough piece of work," he said.

He said it only got made because Channel 4's commissioning editor of drama, Lee Mason, "literally put the script in his drawer and waited for all the staff to change and all the heads of department to move on and then got the script out again and said: 'Would you like to make this?'"

Davies said he had planned it as eight-part version but he was asked by Channel 4 to whittle it down to five.

What have the reviews been like?

The series has attracted widespread praise from TV critics including The Guardian's Lucy Mangan, who gave it five stars, describing it as "a companion masterpiece" to Davies' earlier work, Queer as Folk.

The Evening Standard's Nandy Durrant gave it four stars and called it, "poignant, shocking and will leave you sobbing into your coconut cocktail".

The Independent's TV Critic Ed Cumming also gave It's A Sin four stars, writing: "For anyone who's been through the agony of coming out, especially to a hostile family, or who lost loved ones to Aids, I expect it will be moving."

Celebrity fans have also lavished the series with praise.

Graham Norton described it as "the best five hours of television I've seen in years".

Sir Elton John said it was "a triumph of creativity and humanity" in his post on Instagram.

"Watching it, so many sad and devastating memories came flooding back," he wrote.

TV cook and author Nigella Lawson said she was "lost for words", adding that it was a "masterpiece".

RuPaul's Drag Race star Michelle Visage described it as simply "so, so good".