IT is home to the world’s most historic golf courses, including the Royal and Ancient Golf Club of St Andrews. To date, the St Andrews Golf Links has held 29 Open Championships – more than any other golf club across the world.

Behind every great golfer is a great caddie. Be it entertainer, adviser, chaperone or trainer, caddies are the unsung heroes of the course. Until now. Loopers: The Caddie’s Long Walk is the first feature-length exploration into the personal bond shared by a golfer, a caddie and the course, narrated by the most famous member of the Caddie Hall of Fame, Bill Murray.

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“A caddy is akin to having a legal, extra club in your golf bag,” says Robert Jenkins, of Royal Troon, a former Spanish Senior Champion.

“His experience is invaluable with such issues as the importance of reading greens, helping you keep composure under pressure – keeping quiet and you calm when things are not going your way.”

So, what is it really like to be a caddie?

“There’s the guy who wants me to just turn up and just shut up,” says caddie Gordon Rorison, from Pebble Beach Golf Links in Carnoustie. “All he wants is the information, and that’s what he’s going to get. If he wants to talk about Scotland and stories about caddies, then that’s also what he’s going to get.”

Findlay Jardine is a former pro golfer who has caddied on some of Scotland’s best courses, including Loch Lomond, Crail and Loch Ness.

“It didn’t help my game at all,” Jardine laughs. “If you’ve been out there for four and a half hours watching some guy chunk it all over the place, the last thing you want to do is play a game yourself.

“It’s good fun though.”

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Being a caddie is not just lugging a bag about, contrary to what it may look like from the outside. The caddie knows the course intimately and can be the difference between a good or bad game. If you have a decent caddie, you can save 10-15 shots per round.”

“Some players just want to be having the craic with their buddies,” Jardine tells me. “Others want input from you, history; they want jokes, to be entertained.”

Does the “show up, keep up and shut up” attitude ever prevail on a Scottish course?

Jardine explains: “Sometimes. You do get the occasional asshole, but then you just have to remind them that the bag is heavy and if they’d rather carry it themselves …”

“It’s probably one of the most infuriating games, but it has the best ambience of any other game on the planet. It’s you’re against the golf course, you’re against your brain – it’s a difficult game to play and comprehend for some people. The fun thing is actually having to help someone as best you can.”

Loopers is screened at the Edinburgh Film Festival today at 3.45pm in the Odeon 4, Edinburgh. It is released on September 3