Grab the tissues because this film is going to make you weep.

Stanley Tucci and Colin Firth will star as Sam and Tusker, partners of 20 years, in the emotionally-charged new film Supernova.

The film follows the couple as they travel across England in their campervan two years after Tusker was diagnosed with young-onset dementia.

“As the trip progresses however, their individual ideas for their future begin to collide,” a description of the film reads. “Secrets are uncovered, private plans unravel and their love for each other is tested like never before. Ultimately, they must confront the question of what it means to love one another in the face of Tusker’s irreparable illness.”

Supernova was written and directed by Harry Macqueen (Hinterland), and from the award-winning producers of 45 Years and I Am Not A Witch.

This first UK trailer shows that the film is set to become one of the most poignant same-sex love stories ever portrayed on the big screen.

Supernova will celebrate its World Premiere at San Sebastián International Film Festival this week on 24 September, before heading to the BFI London Film Festival on 11 October.

The film will then be released in cinemas in the UK on 27 November.