Russell Brand took to his YouTube channel on Friday to ‘absolutely deny’ what he called ‘serious allegations’ made against him in a letter and email – ahead of a mystery Channel 4 Dispatches investigation.

The much-anticipated programme is set to air at 9pm on Saturday night, with speculation building over who or what could be at the centre of the investigation.

Sources say that the long running current affairs documentary series will feature details about a well-known celebrity, which the Mail have been told are shocking.

Though there is no indication Brand will be covered in the programme, he made a video addresses his fans. 

The comedian, actor and internet personality told his 6.5 million subscribers late on Friday night that there are ‘very, very serious criminal allegations’ made against him which he ‘absolutely refutes’.

Brand said he had received two ‘extremely disturbing letters’ from a ‘mainstream media TV company’ and a newspaper.

The letters listed ‘a litany of extremely egregious and aggressive attacks, which are untrue’, Brand said.

Russell Brand has taken to his YouTube channel to ‘absolutely deny’ what he called ‘serious allegations’ ahead of a mystery Channel 4 Dispatches investigation

‘These allegations pertain to the time when I was working in the mainstream, when I was in the newspapers all the time, when I was in the movies. And as I’ve written about extensively in my books, I was very, very promiscuous.’

He goes on to say relationships he had during this time were ‘always consensual’.

‘I was always transparent about that. Then almost too transparent, and I’m being transparent about it now as well,’ he said.

‘And to see that transparency metastasized into something criminal that I absolutely deny makes me question, is there another agenda at play?’

Brand closes the video, which has had more than a million views since it was uploaded to X two hours ago, by saying: ‘In the meantime I want you to stay close, stay awake, but more importantly than any of that – if you can, please – stay free.’

‘Stay free’ is a phrase he frequently used to ends his videos on his channel. 

Brand’s statement came amid rumours on social media about whether a scandal about a famous person could feature in the investigation airing today.

The Channel 4 TV guide simply lists the hotly-anticipated programme as ‘New: Dispatches Special. A 90-minute special Dispatches investigation’.

The comedian, actor and internet personality told his 6.5 million subscribers that there are ‘very, very serious criminal allegations’ made against him which he ‘absolutely refutes’

The network confirmed on its online listings yesterday morning that they were showing it at 9pm on Saturday night. 

Now, a link to the programme page comes up with a message saying: ‘That page cannot be found. Either the address is incorrect or the page is no longer available.’

Radio Times magazine also had the programme in this week’s listings, with the description: ‘Dispatches – Investigation series covering issues in British society, politics, international current affairs, health, religion and the environment.’

The programme is due to finish at 10.30pm, but will also be repeated on Channel 4 on Sunday at 10.50pm and on Monday on its sister channel 4seven at 9pm.

Among those posting an image on X, formerly Twitter, of the description on the Channel 4 TV guide was the broadcaster’s news anchor Krishnan Guru-Murthy, who said: ‘Something’s up’ before quickly deleting the message.

The Channel 4 News anchor and Strictly star’s post fuelled more speculation about the 90-minute special. He tweeted a picture of the schedule alongside the caption: ‘Something’s up’ before deleting it around an hour later. 

Sources close to Mr Guru-Murthy, 53, who has worked for Channel 4 for 25 years, said that he was told to take it down as the nature of the programme is ‘sensitive.’

Channel 4 News presenter Krishnan Guru-Murthy posted on X, saying: ‘Something’s up’

The Channel 4 TV guide simply lists a ’90-minute special Dispatches investigation’ tomorrow

Dispatches has screened various big investigations in recent years.

In July 2018 it revealed for the first time how Facebook decides what users can and can’t see on the platform and in 2021 television presenter Davina McCall fronted a programme on the menopause.

In 2005 an episode named Undercover Teacher saw a qualified science teacher, Alex Dolan, going undercover in schools in Leeds and London to expose the ‘appalling teaching’.

Channel 4 has not yet returned MailOnline’s request for comment.