Two stars of Celebrity Traitors complained to producers after finding the process of this year's show gruelling, according to reports. 

The show, which will return to screens on October 1, will see 21 celebrities go head-to-head in the ultimate game of treachery and betrayal. 

But two of the stars are said to have struggled with the nature of the game early on and complained to studio bosses during filming. 

A TV insider told The Sun: 'Different moments can affect some more than others, but the producers are very understanding and make every effort to counter concerns or issues.

'There certainly wasn't an attempt to make the show any more challenging than last year's. But the whole point of the game is that it's a challenge.

'At any point contestants are obviously free to leave the process and producers would not want anyone to be there under sense of obligation.

'All they care about is the safety and welfare of everyone.'

A spokesman for The Celebrity Traitors told the Daily Mail: 'The Traitors is a unique and immersive game and whilst we recognise that taking part can be intense at times, we want everyone to have the best experience possible so the door will always remain open for players to feed back.'

Joining host Claudia Winkleman in the Scottish Highlands are Amol Rajan, Bella Ramsey, James Acaster, James Blunt, Jerry Hall, Joanne McNally, Joe Lycett, Julie Hesmondhalgh, King Kenny and Leigh-Anne Pinnock.

Maya Jama, Michael Sheen, Miranda Hart, Myha'la, Professor Hannah Fry, Richard E Grant, Rob Beckett, Romesh Ranganathan, Ross Kemp, Sebastian Croft and Sharon Rooney complete the line up. 

A new explosive trailer released showed the stars meeting each other for the first time at the iconic castle as host Claudia declared: 'The game is on!'

A trailer hinted at the difficult tasks the group had to endure with an exploding pirate ship as the stars have to try and build up the £100,000 cash prize for a chosen charity.

The new trailer showed the players arriving to the castle in their swanky cars before heading to a church as they all take their seats for the first task. 

Maya then quipped to her fellow players: 'If this is the last time we are all friends, then good luck!'

The trailer then cut to the first tense Round Table as Claudia told them: 'I have chosen my Traitors. The game is on!' 

She added: 'There are now killers among you. People are out there to deceive. Fame won't save them.'

The series will begin with an extra-long opening episode and the launch night will also see a new bonus special airing.