This quiet, heartfelt film has some big accomplishments. It's the story of a liberal, left leaning cynic and a trusting, uneducated senior – The Guardian and the Daily Mail, if you like – on a quest to find the resolution of a mystery.

Among the accomplishments is that even though (if you're a film fan) you're likely to identify more with journalist Martin (Coogan) than retired nurse Philomena (Dench), it doesn't let you pity, laugh at or demonise her point of view.

Even the terminally wry Martin is won over when the working class, salt-of-the-Earth old Irish lady is revealed to be just as smart as Martin in her own way. It's almost as if the pair combine to make a perfectly rounded whole, with both the trusting nature we'd all like and the critical faculties we all try to maintain.

Martin, a formerly well-connected political reporter who's fallen from grace in a scandal, is at a loose end when a friend suggests he look into a human interest story. An elderly Irish woman has come forth for the first time to tell about the baby she had while in a convent who's now turned 50 years old, and she'd like to find him.

Martin considers the story beneath him until he sniffs out an anti-church angle. The cruel nuns who ran the workhouse-like establishment took any babies the girls under their care gave birth to (Magdalene Sisters-style) and sold them to rich Americans.

To Martin it's a chance to reveal the human face of an institutional crime, so he agrees to join Philomena on the search for her now grown son somewhere in America.

It's a journey that will change them both and show them friendship in the unlikeliest of places in classic Hollywood tradition, although it's done with a lot more maturity, subtlety and authenticity than most American writers or directors would usually command.