Peaky Blinders
Cillian Murphy in Peaky Blinders BBC Two

The new Peaky Blinders trailer has confirmed that season four will be full of twists and turns, despite the BBC not announcing a release date as of yet.

A new teaser clip of the Cillian Murphy-led series dropped today, insinuating that gang leader Tommy Shelby (Murphy) could be a traitor and that Alfie Solomons (Tom Hardy) is possibly in danger.

The series is set to pick up six months later from where the last season ended, where some of the gang were arrested and led away in handcuffs after Tommy shopped them to the authorities.

The fourth series will pick up six months after we last left them, with Tommy received a mysterious letter on Christmas Eve which tells him that the Peaky Blinders are in "danger of annihilation," the BBC teases.

The new trailer casts doubt on whether some of the key figures in the Blinders gang are working with him or perhaps conspiring against him.

Murphy, 41, riled up PB fans ahead of the upcoming offering, which stars both Tom Hardy and newcomer Adrien Brody, stating: "I think season four will be the best it has been. I'm very excited about it, I think people will be in for a lot of surprises."

Tommy can be heard saying in the trailer: "The killing of Alfie Solomons is not going to help. This will be very bad for business."

The teaser comes just one month after the first official trailer for Peaky Blinders on 29 September. While Hardy will make a dramatic comeback as Jewish gang leader Alfie Solomans, it seems as though Polly Gray (Helen McCrory) could be facing the end of the road in the fourth season as she faces the death penalty.

The BBC previously teased that the new series will open with Tommy receiving a mysterious letter on Christmas Eve which tells him that the Peaky Blinders are in "danger of annihilation".

"As the enemy closes in, Shelby flees his country house and returns to the streets of Small Heath, Birmingham where a fight for survival begins..." they said.

Murphy also reveals that the Blinders may be getting a taste of reality after the last glitzy season. He told radio station Today FM: "In the classic gangster arc, the last season was sort of all about the wealth, the house and all that material stuff.

"This season is sort of a return to the roots. That's about as much as I can reveal."