The 15:17 to Paris

Cert: 15A. Now showing.

If asked who’d play you in the story of your life, the one person you’d naturally rule out is yourself.

You can sympathise only so much with Spencer Stone, Anthony Sadler and Alek Skarlatos, the young US backpackers who in 2015 helped overpower a terrorist on board a train bound for the French capital. In a move that never looked like it was going to work out, director Clint Eastwood cast the three nonactors in a depiction of the real-life incident. What was he thinking?

Eastwood’s red-state sensibilities are writ large over the project. Flashback scenes in “guns ‘n’ prayers” California show the boys meeting and bonding over a healthy disdain for authority and that love of ammo and warfare that we find baffling in this part of the world.

Stone and Skarlatos fulfil their ambitions to enlist and serve, with the former — the narrative axis of the film — having to bust a gut to reach his potential. They convene in Europe for some inter-railing, taking selfies and getting smiles from waitresses, all the while sighing lines like “you ever feel like life is catapulting you towards a higher purpose?” You can almost locate the point where Eastwood and the acting coaches give up and tell the men to just say the lines on the page.

By the time they’re wrestling with a “generic Islamist baddie”, you’ve forgotten the glimmers of hope early on where an effective sense of the everyman was transmitted by Eastwood. You just want it all to stop and for real actors and scriptwriters to be parachuted in.