How producers keep Broadchurch and other TV shows a secret

Usually, journalists and writers get to see the first episode of a new TV series or a preview of a new film.

It creates buzz, garners publicity and gets the promotion so people watch it or go to see it. Obviously.

But Broadchurch has taken a different stance with no official previews of season two. None. Nada. Zilch. Repeat - none.

Secrecy around the new series has been immense with hardly anything slipping out.

Even the show's cast has been frozen out.

Arthur Darvill, who plays Reverend Paul Coates, told Good Morning Britain: "None of us have seen it. We haven't had a screening.

"I'm not allowed to talk about it."

While a trailer has hinted at what's in store, most of us are none the wiser about how it will pan out.

Will there be another whodunnit? Will it continue where season one left out or will it flash forward in time? Will there be much focus on Olivia Colman's orange jacket?

As a result, the producers of Broadchurch put several measures in place during the filming of season two:

• Non-disclosure agreements were signed by all cast, crew and production meaning any actor who decides to let something slip was probably at risk of getting fired.

• Broadchurch was written and filmed under a secret name, so this meant all scripts, call sheets and locations were referred to under a codename.

• There was security on set while filming in external locations so no local residents of West Bay in Dorset (where Broadchurch is filmed) could get in on the act.

• All scripts had the individual's name stripped across every page meaning no piece of paper could be leaked without a name on it.

Those measures are not exclusive to Broadchurch so we had a look at other famous examples of TV shows which have had to stop a secret getting out.

EastEnders: Who killed Lucy Beale?

The identity of Lucy Beale's killer has been kept a secret

Lucy Beale's killer has been at large since Good Friday 2014. Talk about stringing it out.

One of the reasons the secret of who did it hasn't got out is that the actor playing the killer hasn't even been told.

That actor will be informed in the coming weeks ahead of the big reveal.

The killer will be unveiled as part of a flashback episode during the show's 30th anniversary week on 19 February.

Apparently, the soap's executive producer Dominic Treadwell-Collins has only let three writers in on the secret meaning most people involved in EastEnders are still in the dark.

Friends finale

When one of the world's biggest TV series comes to an end, it's an understatement to say it was a big deal.

The producers of Friends didn't want spoilers of the show's finale getting out so tight security was wrapped around some of the final scenes.

Friends was usually filmed in front of a live audience that was made up of members of the public.

However, the audience for the hour-long show consisted only of specially-invited guests.

Some scenes were also filmed beforehand to keep it secret - we're presuming Rachel (Jennifer Aniston) arriving back at Ross' (David Schwimmer) apartment was one of them.

Doctor Who

Peter Capaldi and Jenna Coleman filming Doctor Who

Anyone who works on Doctor Who knows the entire production is one big secret.

The cast and crew say it's more than their career's worth to let out any plot details, however minor they may seem.

When singer Foxes appeared on the most recent series we asked her what she could tell us about her experience.

"You just can't talk about it," she said. "I wasn't taking pictures because you're not really allowed. But I was in the Tardis freaking out."

The Apprentice

In the early days of the Apprentice, the final prize used to be a £100,000 job working for one of Lord Sugar's companies.

As the whole series was filmed months before transmission, the two finalists would BOTH film an initial ending in which they were told that they'd been hired.

In the months between filming and it going out on TV, the finalists would then both work for Alan Sugar.

Only when the final was about to be transmitted would he tell them who had the job.

It meant that for a long period of time, Lord Sugar was usually the only one to be in on the secret.

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