However, with GHQ harbouring doubts, the future of the regiment hangs in the balance.

Joining O'Connell and Swindells are returning cast members Dominic West, Sofia Boutella and Theo Barklem-Biggs, while new additions to the cast include Gwilym Lee and Con O'Neill.

But who else stars in the series and who do they all play? Read on for everything you need to know about the cast of SAS Rogue Heroes.

SAS Rogue Heroes cast: Full list of actors and characters

The following stars feature in the SAS: Rogue Heroes cast for season 2.

• Jack O'Connell as Paddy Mayne
• Connor Swindells as David Stirling
• Sofia Boutella as Eve Mansour
• Dominic West as Dudley Clarke
• Gwilym Lee as Bill Stirling
• Theo Barklem-Biggs as Reg Seekings
• Corin Silva as Jim Almonds
• Jacob Ifan as Pat Riley
• Jacob McCarthy as Johnny Cooper
• Stuart Campbell as Bill Fraser
• Bobby Schofield as Dave Kershaw
• Mark Rowley as Jock McDiarmid
• Jack Barton as John Tonkin
• Con O’Neill as General Montgomery

These are some of the additional stars who featured in season 1:

• Alfie Allen as Jock Lewes
• Tom Glynn-Carney as Mike Sadler
• Dónal Finn plays Eoin McGonigal
• Amir El-Masry as Dr Gamal

Here is all you need to know about the major players...

Connor Swindells plays David Stirling

Who is David Stirling? David Stirling was the real-life founder of the SAS, who when we first met him in the series was an eccentric young officer serving with 8 Commando. He was frustrated with the military authorities and their handling of strategy.

At the end of season 1 he was captured, and in season 2 is seen in a prisoner of war camp.

Talking to Radio Times magazine about how making this BBC drama compared to making Sex Education, Swindells said: "Incomparable!

“Sex Education for the most part is me going to Wales a couple of times a week, saying absolutely nothing, pulling a funny face and then driving home. So being out in the desert was unbelievable. But, thankfully, I made great friends for life.”

What else has Connor Swindells been in? Swindells is best known for playing Adam Groff in Sex Education but has also had roles in the series Vigil, Jamestown and The Completely Made-Up Adventures of Dick Turpin, as well as the films Emma, Barbarians, Barbie and Scoop.

Dominic West plays Dudley Clarke

Who is Dudley Clarke? Dudley Clarke was a real-life officer in the SAS and is considered a pioneer in military deception.

Dominic West says of his character: "Dudley Clarke is the man who came up with the idea of the Special Air Service, he named it the SAS. But it was just a propaganda tool before Stirling came along and made it real – so he reckons he invented the SAS, and that’s good enough for me."

What else has Dominic West been in? West is a prolific and acclaimed actor known for series such as The Wire, Brassic, The Affair and The Agency, as well as films Downton Abbey: A New Era, Tomb Raider, 300 and Pride. He also played Charles, Prince of Wales in seasons 5 and 6 of The Crown.

Gwilym Lee plays Bill Stirling

Who is Bill Stirling? Bill is David Stirling's older brother, who at the start of season 2 approaches Paddy Mayne about the future of the SAS. In real life, Bill founded the 2SAS, and in the series he is seen as Paddy's link to GHQ.

What else has Gwilym Lee been in? Lee has had roles in series including Fresh Meat, Midsomer Murders, Jamestown and The Great, as well as films such as Bohemian Rhapsody and Here.

Jack O'Connell plays Paddy Mayne

Who is Paddy Mayne? Paddy Mayne was a real-life British army officer and a founding member of the SAS. He is portrayed in the series as something of a live-wire, who was won around by David Stirling.

In season 2, he has taken command of the SAS, after David was captured.

Speaking about returning as Paddy for season 2, O'Connell told the BBC: "I love this character, in terms of the man himself we can do all the research in the world but at the end of the day it’s what Steven Knight has offered on page that has to be the main guidance. We do obviously tell a historical tale but it’s quite reimagined, there’s a lot of room to play with within that."

He continued: "Reading series two it feels like a continuation. When the scripts came through we were all buzzing, it’s got Steven Knight’s imprint on it and the scripts were banging."

What else has Jack O'Connell been in? O'Connell is known for appearing in films such as Unbroken, '71, Lady Chatterley's Lover, Ferrari and Back to Black, as well as the series Skins, Godless and The North Water.

Corin Silva plays Jim Almonds

Who is Jim Almonds? Jim was a real-life member of the SAS, who in the series Paddy trusts completely, and often views as his conscience and a grounding force.

What else has Corin Silva been in? Silva has appeared in series such as The Bay, All the Light We Cannot See, Masters of the Air and Stags.

Jacob Ifan plays Pat Riley

Who is Pat Riley? Pat Riley was a real-life member of the SAS in the Second World War.

What else has Jacob Ifan been in? Ifan has appeared in series including Cuffs, Bang, A Discovery of Witches, The Pact and Tree on a Hill.

Theo Barklem-Biggs plays Reg Seekings

Who is Reg Seekings? Reg Seekings was a real-life founding member of the SAS.

What else has Theo Barklem-Biggs been in? Barklem-Biggs has had roles in series including EastEnders, Silent Witness, The Fades, Silk, Cleaning Up and Carnival Row, as well as films such as The Inbetweeners Movie, Kingsman: The Secret Service, Journey's End, Femme, Cherry and The End We Start From.

Jacob McCarthy plays Johnny Cooper

Who is Johnny Cooper? Johnny Cooper was a real-life officer who served with the SAS in North Africa and France throughout World War II.

What else has Jacob McCarthy been in? McCarthy is known for appearing in films such as The Tragedy of Macbeth and The Last Summer and series including AP Bio and Mary & George.

Sofia Boutella plays Eve Mansour

Who is Eve Mansour? Eve is a fictional character created for the series. She is the deputy head of French intelligence in Cairo under General de Gaulle’s command and does not play by the rules.

"Even if Eve is a fictional character in comparison to David Stirling or Paddy Mayne, she is very much a character that existed at the time," reveals Sofia Boutella.

"There were spies like Noor Inayat Khan or Virginia Hall. So many incredible women who were a part of the liberation during the Second World War. Eve, like a lot of them, used methods that were born within her instinct and her intelligence."

What else has Sofia Boutella been in? Boutella is known for appearing in films such as The Mummy, Atomic Blonde, Star Trek Beyond, Kingsman: The Secret Service, Argylle and both part of Rebel Moon, while she also recently appeared in an episode of Guillermo Del Toro's Cabinet of Curiosities.

Stuart Campbell plays Bill Fraser

Who is Bill Fraser? Bill was a real-life member of the SAS in the Second World War.

What else has Stuart Campbell been in? Campbell is best known for appearing in series such as Baptiste, Clique, Hetty Feather, Professor T, The Winter King and Shetland.

Bobby Schofield plays Dave Kershaw

Who is Dave Kershaw? Dave was a real-life member of the SAS.

What else has Bobby Schofield been in? Schofield is known for his appearances in The Walk-In, The Suspect, Anne and Eric, while he also appeared in an episode of Inside No 9 amongst other series.

Jack Barton plays John Tonkin

Who is John Tonkin? John Tonkin was a real-life member of the SAS.

What else has Jack Barton been in? Barton has had roles in series such as Grantchester, War of the Worlds and Heartstopper, as well as the film Poor Things.

Con O’Neill plays General Montgomery

Who is General Montgomery? General Montgomery was a Senior British Army officer. In the series, he has the fate of the SAS as a unit in his hands.

What else has Con O'Neill been in? O'Neill is known for his roles in series including Uncle, Chernobyl, COBRA, Without Sin, Nolly, Happy Valley, Our Flag Means Death and The Penguin, as well as films such as The Batman.

Mark Rowley plays Jock McDiarmid

Who is Jock McDiarmid? Jock was a real-life member of the SAS in the Second World War.

What else has Mark Rowley been in? Rowley is best-known for his role in The Last Kingdom, while he has also appeared in series including Luther, The Spanish Princess, The Witcher: Blood Origin and One Day.

Season 1 characters

Alfie Allen plays Jock Lewes

Who is Jock Lewes? Jock Lewes was the real-life founding principal training officer of the SAS, who at the start of the series shared with Stirling his idea of parachuting units of men into the desert to attack by surprise.

"He was pushing the boundaries in terms of what he would make his men," notes Allen to the BBC.

Talking to Radio Times magazine about how making this BBC drama compared to Game of Thrones, Allen said: “This was totally different. Completely different surroundings – and it was hot! In terms of the environment, it was definitely still challenging.”

What else has Alfie Allen been in? The son of Keith Allen and brother of Lily, Alfie Allen is best known for his role as Theon Greyjoy in Game of Thrones. He has also appeared in White House Farm, John Wick and The Predator, amongst other series and films.

Tom Glynn-Carney plays Mike Sadler

Who is Mike Sadler? Mike Sadler is a real-life figure and was one of the first officers to join the SAS.

What else has Tom Glynn-Carney been in? Glynn-Carney is currently starring in House of the Dragon as Prince Aegon Targaryen, while he has previously appeared in The Last Post, The King, Tolkien, Dunkirk and The Jetty.

Dónal Finn plays Eoin McGonigal

Who is Eoin McGonigal? Eoin was a real-life member of the SAS in World War II and a close friend of Paddy Mayne.

What else has Dónal Finn been in? Finn had a small role in Fantastic Beasts: The Secrets of Dumbledore and has appeared in episodes of The Wheel of Time and The Witcher.

Amir El-Masry plays Dr Gamal

Who is Dr Gamal? Dr Gamal is a doctor in Cairo and an ally of Stirling.

What else has Amir El-Masry been in? El-Masry is best known for starring in the film Limbo, while he has also had roles in McMafia, The Night Manager and Industry. He also had a small role in Star Wars: The Rise of Skywalker and played a young Mohamed Al-Fayed in flashbacks for season 5 of The Crown.

Read more:

• SAS Rogue Heroes true story: How much of the drama really happened?
• SAS Rogue Heroes soundtrack: Every song featured in the drama

SAS Rogue Heroes season 2 will air at 9pm on New Year's Day on BBC One and BBC iPlayer, while season 1 is available on BBC iPlayer now.

If you're looking for something else to watch, visit our TV Guide or take a look at the rest of our Drama coverage. For more from the biggest stars in TV, listen to The Radio Times Podcast.