Image copyright Channel 4 Image caption Channel 4's Smuggled followed members of the public as they tried to evade border checks

Channel 4 has postponed the broadcast of a new documentary after 39 bodies were discovered in a lorry in Essex.

Smuggled was set to follow eight members of the public as they tried to enter the UK from Europe by evading border checks.

A spokeswoman said: "In light of the tragic events today we have postponed the transmission of the series."

The 39 people found dead in the refrigerated trailer were Chinese nationals, it is understood.

In promotional material, Channel 4 said it had commissioned the show at a time when the UK was preparing to "take back control" with Brexit and described the programme as an "unprecedented national security experiment".

Media playback is unsupported on your device Media caption Aerial footage shows police activity around the lorry where the bodies were found

A press screening of Smuggled had been planned for Thursday but was cancelled after the discovery of the bodies in the early hours of Wednesday.

Essex Police initially suggested the lorry could be from Bulgaria, but later said officers believed it entered the UK from Belgium. The lorry was found at Waterglade Industrial Park in Grays, Essex and police said 38 adults and one teenager were pronounced dead at the scene.

Holding back

This is far from the first time a TV network or film studio has pulled the broadcast or release of certain projects after a real-life tragedy has hit the headlines.

A movie or TV series which unintentionally reflects a recent horrific event can feel insensitive or distasteful - and they often end up being reshot or rescheduled as a result.

Image copyright Getty Images Image caption A trailer for a film starring Betty Gilpin (left) and Hilary Swank was pulled after the El Paso shooting

In August, Universal Pictures cancelled the release of horror movie The Hunt, which was set to star double Oscar winner Hilary Swank and Glow's Betty Gilpin.

The satirical and gory film told the story of liberals who hunt Trump supporters and kill them for sport, a storyline intended to reflect the divided nature of politics at the moment.

But after the shootings in El Paso, Texas and Dayton, Ohio, the trailers were taken off air - including one which opened with the sound resembling an emergency broadcast signal - before the film was pulled altogether.

A statement from Universal at the time said: "We stand by our filmmakers and will continue to distribute films in partnership with bold and visionary creators, like those associated with this satirical social thriller, but we understand that now is not the right time to release this film."

Image caption Bastille Day, Shooter and Gone Baby Gone have all faced delays because of real-life events

Other films to have been affected by real-life tragedies include Bastille Day, which starred Idris Elba.

But the film, which was about civilians killed by a bomb explosion in Paris, was pulled from cinemas in France the day after it was released because of the 2016 terror attack in Nice.

StudioCanal stopped adverts for the film immediately after the attack and soon cancelled its release altogether, commenting that it was "not in line with the national mood".

"Studios, like many major corporations, are risk averse," says Andreas Wiseman, international editor at Deadline.

"The performance over its opening weekend can often make or break a film, so distributors spend a long time strategising over an optimum release date.

"If there is a chance a social or political context might turn media or audiences against a film, studios will reroute."

Image copyright Warner Bros Image caption An episode of Friends was reshot after the 9/11 attacks

The studio's request to pull Bastille Day out of French cinemas was supported by the film's lead actor. Elba told The Sun that the producers probably thought the film was "insensitive" and did not "feel right to have out there".

Yet some French film fans were disappointed with the studio's decision. One told Reuters he "didn't make the connection with Nice".

"There are so many differences," said the cinemagoer. "I think it's a coincidence and I find it a shame for the people who made the film."

Producing a film or TV series is a long and laborious process - the whole operation can often take years.

So when a project is thrown into uncertainty as a result of reality, studios often try to just delay (rather than cancel) its release.

In 2017, a remake of Death Wish was pushed back by several months after a mass shooting in Las Vegas.

And TV series Shooter - a drama about a sniper - was postponed after unrest prompted by the shooting of black men by police.

Image copyright Getty Images Image caption Ryan Phillippe starred in Shooter, which was also postponed

USA Network initially delayed the show's debut by a week - and "after further consideration", it was subsequently postponed until the autumn.

Paris-based film journalist Lisa Nesselson, who saw Bastille Day in a French cinema after the Nice attack, says she is unsure whether TV networks and film studios should react in the same way.

"I don't know if films are delayed or pulled out of respect for terror victims, or because it's assumed that nobody will be in the mood to see that topic or a little of both," she says.

"I might be in favour of changing television programming in deference to a violent national event," she continues.

"But I find it much harder to grasp why a movie that requires an individual to make the decision to pay to get in should be punished for being about the 'wrong' thing at a particular moment in time."

Perhaps the biggest single event of recent times to affect the film and TV industry was the 9/11 attack in 2001.

Image copyright Getty Images Image caption A 2017 remake of Death Wish starring Bruce Willis was postponed

A scene in Spider-Man featuring the twin towers of New York's World Trade Center was deleted from the film and the trailers in light of the sombre national mood, and the location was also edited out of Men In Black II and Zoolander.

Friends - one of the most successful TV sitcoms of all time - cut an entire storyline from one episode which saw Chandler detained at an airport after making a joke about a bomb.

It was replaced by a new storyline involving Monica and Chandler, and the already-filmed footage was only released years later as part of a box set.

In the UK, one of the longest delays to a major film came in 2007 when Gone Baby Gone was due to be released.

It came out in the US in October and was set for a UK release in December - but was halted by the disappearance of Madeleine McCann as the producers felt the plot, which dealt with a young girl going missing, was distasteful.

Image copyright Getty Images Image caption Ben Affleck directed Gone Baby Gone, whose release was postponed in the UK

Wiseman says that while audiences like to identify with characters and storylines, a story which appears to reflect a real-life horror can be difficult to watch.

"Hollywood studios want and need audience identification in their films, but too much identification can become uncomfortable for some unsuspecting viewers who find material too close to real-life tragedy."

He adds that once promotion has begun, films can be more difficult to change or postpone than TV shows.

"Delays can be very costly, especially if they happen after advertising has already been booked and campaigns are under way.

"If a campaign is fragmented or becomes confused in its timing, then audiences are likely to find something else to watch."

However, he says it "can work both ways".

"While many films about terrorism were shelved around 9/11, a whimsical and sweet film like Amelie unexpectedly took off in the US and in many other countries [because] audiences wanted a joyful escape."

Earlier versions of this article have previously appeared on the BBC News website.

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