Murphy, 48, portrays father Bill Furlong in the movie, which is based on Claire Keegan's best-selling book of the same name about Ireland's infamous Magdalene Laundries.
"We really tried to be faithful to the script itself, or, I should say, to the book itself," Murphy stated while posing on the red carpet at the movie's UK premiere in London.
"Because the novella is so exquisite, exquisite, and flawless. "I believe that staying true to the text was our largest obstacle.
"And then we just wanted to tell the story in a gentle, delicate way, leaving enough space for the audience, really, to come into it to find their own way into the stories."
The movie centres on Bill, who supports his family by working as a coal trader and learns about the treatment of mothers and infants at a monastery in New Ross, County Wexford.
#CillianMurphy at the Premiere of Small Things Like These pic.twitter.com/4Bt80GhYDD
— Marty (@MartinaDi33420) October 24, 2024
Nuns ran launderettes throughout Ireland starting in the 18th century, and the last one, located on Sean McDermott Street in Dublin, closed its doors in 1996.
In the 20th century, the laundry's purpose was broadened from serving "fallen women" to include women who had not been pregnant or who had come from children's homes.
Unmarked graves were found at one location in the 1990s, and the facilities gained notoriety for the cruelty that many women endured there. In 2013, the State formally apologised for the problem.