Both the stars took to their Twitter accounts to unveil the new posters.
Abraham shared a picture of himself in an Army uniform looking fierce and serious, captioning it as, "Join Ashwat in his mission. #Parmanu
Meanwhile, his co-star Penty also shared a similar snap in the same army gear of herself from her account.
She captioned the post as, "There is no stopping Ambalika. #Parmanu @ParmanuTheMovie @kriarj"
The 'Cocktail' actress had a grim expression in the new poster and looked totally different from the characters she had played in her previous films.
This would be the first time for the co-stars to be paired for a film together.
The film is based on the nuclear bomb test explosions conducted by India at the Indian Army's Pokhran Test Range in 1998.
The movie is directed by Abhishek Sharma and produced by Zee Studio, JA Entertainment and Kriaj Entertainment.
'Parmanu: The Story of Pokhran' also features Boman Irani in a pivotal role, is all set to hit the theatres on December 8.