Irn-Bru is turning the clock back more than a century, months after warning of plummeting profits.
Drinks maker AG Barr is to launch a limited edition new version it claimed was based on an original recipe from 1901.
It comes three months after it warned profits were being hit by customers turning away from its reduced-sugar drinks.
The firm said Irn-Bru 1901 - to hit shelves in December - was made from a handwritten recipe which had been "stored deep in the company archives for over 100 years".
Without caffeine, the drink is sweetened with sugar and "does have a frothy head on its gingery fizz".
Robin Barr, who unearthed the recipe, said: "The 1901 recipe has aged beautifully over the last 118 years.
"For a limited time, we'll be producing a premium 'old and unimproved' Irn-Bru 1901 just as it was enjoyed by our first fans.
"This is Irn-Bru as you've never tasted it. It's a chance to enjoy a unique and authentic piece of Scottish history - but don't hang about, we don't think it will be around for long."
In July, AG Barr warned sales this year would drop 10% and profits slide by up to 20% as they struggle against a strong year in 2018.
It blamed challenges since the introduction of the sugar-tax levy, with several drinks companies having to change their recipes to reduce sugar levels.
This has led to a backlash among some customers, who have complained about the new tastes.