The reason for that, aside from Dench's acting, is the strength of her story, which has parallels to the tales told in Peter Mullan 's considerably more savage 2002 feature, "The Magdalene Sisters."
The nuns' cruelty to the younger Philomena is akin to what we saw in Peter Mullan's "The Magdalene Sisters" (who are even cited in one scene) and it opens the door for Sixsmith's questioning of the place of religion in modern society.
The depiction of events at the convent brings to mind Peter Mullan's poignant and unflinching 2002 film The Magdalene Sisters which revealed the inhuman treatment of large numbers of "fallen women" in Irish Catholic asylums where they worked in profit-making laundries as virtual slaves.
Star Steve Coogan (various Alan Partridge series and movies) and Jeff Pope ("Pierrepoint: The Last Hangman") have adapted Sixmith's book 'The Lost Child of Philomena Lee' as an odd couple road movie with flashbacks recalling Peter Mullen's 2002 Venice Film Festival winner "The Magdalene Sisters."
Though it flickers with the fury that coursed through Peter Mullan’s The Magdalene Sisters , another film about this chapter in U.K. history, Philomena ultimately strives to be a tale of forgiveness.