Stars from the Games of Thrones prequel have been spotted filming on a beach in Cornwall – and it is thought the shoot may be heading further west after a warning to expect 'plumes of smoke' off Marazion today.

Former Doctor Who star Matt Smith was among the actors photographed at Holywell Bay this week, one of the confirmed locations for the filming of the new series called House of the Dragon.

Based on George RR Martin’s book Fire & Blood, the series will tell the story of House Targaryen, from which Daenerys Targaryen of the original show came from, and will take place 300 years before the events of Game of Thrones.

It is being filmed for American TV channel HBO and it has already been confirmed the ten-episode series, due to air in 2022, will also be available to viewers in the UK also on Sky Atlantic, as well as on NOW.

The cast and crew at Holywell Bay. Picture: SWNS

The cast and crew at Holywell Bay. Picture: SWNS

Matt Smith plays Prince Daemon Targaryen, the younger brother of King Viserys and heir to the throne. He is described in the pre-show press for the series as "a peerless warrior and a dragonrider who possesses the true blood of the dragon."

With him on the beach at Holywell Bay was Emma D'Arcy, whose previous work includes the TV series Truth Seekers alongside Nick Frost. She plays Princess Rhaenyra Targaryen, the king’s first-born child. She is of pure Valyrian blood, and she is a dragonrider.

They could both be seen with very pale blonde hair and thick overcoats as they laughed and joked during a break in filming.

Markers are drawn out in the sand as part of filming. Picture: SWNS

Markers are drawn out in the sand as part of filming. Picture: SWNS

Today it is thought that action connected to the filming of the series will also be taking place on St Michael's Mount.

This is understood to be another location for the shoot, where crew tents and scaffolding has been put up, and photos have emerged of a stone archway showing a logo of the House Velaryon, although so far no actors have been spotted there yet.

Today Cornwall Fire and Rescue Service put out an advanced warning to expect to see smoke coming from the island.

The tweet read: "There will be controlled plumes of smoke on the south side of St Michael's Mount today. This will be on the seaward side and on the cliff edge."

The crew has set up camp on the beach. Picture: SWNS

The crew has set up camp on the beach. Picture: SWNS

It is thought this is connected to the series, although it is not clear at this stage whether the cameras will be rolling for location shots or if is in preparation for future filming.

Signs first emerged that Cornwall had been chosen among the filming locations after a Warner Bros lorry was seen in Newquay.

Warner Bros is owned by WarnerMedia, which is also the parent company to HBO and CNN.