The 11-part series Voices of Liberation is currently in production and filmed at sites across the city this weekend.
Game of Thrones, Love Actually and The Queen’s Gambit star Thomas Brodie-Sangster is taking part in the documentary.
He was pictured at The Careen cafe in Old Portsmouth during a break in filming this weekend.
Brodie-Sangster was seen with a film crew at the Round Tower on Broad Street.
The actor was also spotted filming on a boat and is thought to have carried out more filming at Southsea Castle before heading north.
Voices of Liberation is being written and directed by Belgian filmmaker Koen Mortier who is known for directing Ex Drummer (2007), 22nd of May (2010) and Angel (2018).
According to production company Czar, the documentary series is ‘about the international commemoration route which joins together the important milestones of the Second World War’.
The post on Czar’s website continues: ‘The route forms a chain between the most important regions during the advance of the western allies. The series guides us along this route accompanied by local hosts who each one of them have a link with the Second World War.
‘Along the actual facts told through the use of personal documents (letters, diaries, memoirs, …) they also tell us their personal stories, which offers the public an alternative view of the events.
‘In addition, this television series does not only focus on the story of ‘the Allied liberator’, but also on that of ‘the civilian’, ‘the resistance fighter’, ‘the collaborator’ and even ‘the enemy’.’
Thomas Brodie-Sangster will appear in two of the episodes, while German actor Christian Berkel and many more are also expected to appear in the documentary.
A release window for Voices of Liberation has yet to be announced.