Adam Nagaitis has joined Karen Gillan in 'Gunpowder Milkshake'.

Karen Gillan

Karen Gillan

The 33-year-old actor - who is best known for his roles as Cornelius Hickey in the AMC television series 'The Terror' and Vasily Ignatenko in the HBO miniseries 'Chernobyl' - will appear alongside the 'Avengers: Endgame' star in the forthcoming female-focused assassin thriller, according to Variety.

Angela Bassett and Lena Headey are also set to star and although details of the plot have been kept under wraps, the film is described as being in the assassin genre and includes stories spanning over multiple generations.

The action flick will be directed by Aharon Keshales and Navot Papushado, the pair responsible for the dark Israeli breakout 'Big Bad Wolves' and the duo have also penned the script alongside graphic novel writer Ehud Lavski.

Andrew Rona and Alex Heineman of The Picture Company will produce the movie through their overall deal with Studiocanal.

It was also announced that Nagaitis has bagged a role in Tom Hardy and Steven Knight's adaptation of Charles Dickens' 'A Christmas Carol' for the BBC.

The 40-year-old actor will work alongside the 'Peaky Blinders' and 'Taboo' writer on the adaptation of the novel, which will air on BBC One over the Christmas period in 2019.

Gillan, 31, has had a busy 2019 after starting filming the sequel to 'Jumanji: Welcome to the Jungle' in February and reprising her role as Nebula in Marvel superhero blockbuster 'Avengers: Endgame'

The former 'Doctor Who' star made her directorial feature debut with 'The Party's Just Beginning' last year and the film, written by and starring herself, centres on her character, Liusaidh, dealing with the stress and heartbreak from losing her best friend to suicide.