Welcome the latest Nicholas Sparks adaptation: always the same, always a bit different (but mostly the same). In a corner of Louisiana – where the rougher hicks still dress like the Beverly Hillbillies – James Marsden and Michelle Monaghan play out a midlife variation on Sparks's The Notebook.

Once they were young, besotted and startlingly unlike James Marsden and Michelle Monaghan. He (Luke Bracey) was a smart guy from the wrong side of the tracks; she (Liana Liberato) was the privileged daughter of an archetypal rich snob.

What can have gone wrong? In the present, Marsden works on an oil rig and, to communicate his intelligence to the audience, ostentatiously reads Stephen Hawking books. Monaghan is unhappily married to Frank (Sebastian Arcelus) a walking catalogue of pointers towards malevolence: he plays golf, takes work calls at the dinner table and turns up at hospitals in a state of comic inebriation. Then the death of an elderly pal brings all back to hometown Louisiana. “Hic! Shorry about your friend and all. Hic!” Frank almost says. “But we’ve gotsh that dinner with Mr Bossington. Hic!”

To be fair, the first 90 minutes of The Best of Me are as tolerable as any Sparksiana since The Notebook (still the best adaptation). The binary classification of the characters – there is no middle ground between thumpingly evil and positively saintly – is consistently absurd, but both couples of actors positively throb with warm energy. Then, sadly, it spins off the rails into the most absurdly busy, breathlessly melodramatic 15 minutes you will endure in the cinema this year. Imagine five years of General Hospital packed into 10 minutes of drama. Phew!