The ‘animal-changed-my-life’ subgenre is an old if not particularly distinguished one. Recently, it seems to be enjoying something of a revival, with Steve Coogan starring in The Penguin Lessons and now The Friend, a warm if edgeless adaptation of Sigrid Nunez’s bestseller novel about a New York literary life turned upside down by an orphaned Great Dane.

Naomi Watts and Bill Murray in the film The Friend

Iris (played by Naomi Watts, who has strong form in animal movies – remember Penguin Bloom?) is a writer and teacher living in the West Village. She has a novel of her own on the backburner, but she spends most of her time running writing classes helping others find their voice. Hers is a modest, largely solitary life, but it’s a comfortable one, thanks in no small measure to the fact that she has inherited the lease of a rent-controlled apartment – a vanishingly rare thing in Manhattan.

The ‘Friend’ is Walter (Bill Murray), a renowned American novelist. Actually, make that ‘was’. Not long after we meet him jogging on a cold but sunny day near the Brooklyn Bridge, we...