"It's a funny old comedy about Muslims and Jews", says writer David Baddiel, clearly used to summing up his film in a soundbite.
Director Josh Appignanesi (Song of Songs) is a little less succinct.
"It's about a sort of everyman chap, second generation Pakistani, a lovable guy who's a Muslim in an everyday way. But he finds out he's adopted, and his real name is it's Solly Shimshillewitz and he was born a Jew. That throws him into comic situations".
"With hilarious consequences!" adds Baddiel with a laugh.
Essentially, the message is that we are all the same. One scene shows Mahmud's shock as he enters a synagogue and realises that everyone looks like him.