At the spritely age of 89, Clint Eastwood may well be the last Hollywood screen icon standing. Not only has he made a name for himself as an award-winning actor and director during his illustrious career, he also made the tricky transition, that many still dream of, from TV – in his case, starring in the early sixties hit show Rawhide - to film.

The Mule is yet another one of his projects that he both directs and stars in, loosely based on a true story.

For most of his life, horticulturalist Earl Stone (Eastwood) has devoted all his energy and efforts into his work, sadly at the expense of his family. But when the internet arrives, he soon finds that business quickly dwindling, to the point that his home ends up being foreclosed.

Now, aged 90, he finds himself shunned by the majority of his family members and without a job. But whilst attending a very rare family gathering, which he was invited to by his grand-daughter Ginny (Taissa Farmiga), a party guest suggests a job opportunity for a careful driver. As he has a clean driving record and no tickets ever, he decides to give it a go.

It seems easy enough; he picks up a delivery and drives it for a while to a drop-off point. For that, he gets paid rather handsomely.

Earl is not only unaware of his cargo – a shit load of drugs – but also the interest of new DEA agent Colin Bates (Bradley Cooper) and his right hand man agent Treviño (Michael Peña), who are looking to put a stop to the Mexican cartel flooding the US with their product.

But even when the penny drops, Earl decides it’s all worth the risk, if there’s a chance he can make it up for all the disappointment he’s caused his family.

There can’t be many scripts in Hollywood knocking around for actors nearing their nineties, so it makes sense that Eastwood grabbed this one. Dirty Harry may well be looking frail, but he still manages to sparkle in this curious title. At times, when the camera just rests on him, he radiates the aura of a man that has truly lived.

It’s no surprise that there is still a long line of talent, queuing up to take part in one of his projects, that as well as Cooper and Peña, includes Dianne Wiest, Laurence Fishburne and Andy Garcia.

It’s disappointing then that the mediocre script doesn’t do any of them any justice, including Eastwood. The dialogue is pedestrian at best, lacking the warmth needed to lift the script. The storyline involving his family is all too clichéd, making it really difficult to relate to.

Where it truly falls however is in the relationship between Eastwood and Cooper. It’s introduced all too late, and there was a golden opportunity to develop an intriguing cat and mouse scenario between their two characters, but the route taken instead is rather too obvious and abrupt.

There are also a few scenes that show an elderly Eastwood interacting with scantily clad females, which no-one needed to see.

When he keeps his shirt on though, Eastwood occasionally reveals a welcome playful side, but sadly, these are too few and far between.

Not one of his best then, in either capacity as actor or director, but enough to signal that with more projects on the horizon, there’s still life in this screen icon yet.