The history of a 25-mile (40km) stretch of river is set to be unlocked in a feature-length documentary.
Life on the Deben traces the entire length of the Suffolk river, from disputed upper reaches near Debenham to the boatyards of Woodbridge down to the sea at Bawdsey and Felixstowe.
It has taken two years to make and will be premiered in Woodbridge, close to the river it eulogises, on Sunday.
The team behind the film said it was a call to protect "this amazing asset".
Life on the Deben sees journalist John McCarthy, who was Britain's longest-held hostage in Lebanon, and Woodbridge-based director Tim Curtis explore the chronology of the river from Celtic times to the present day.
Issues which affect the Deben are highlighted in the 90-minute film, including wildlife, conservation, boat building, sailing, farming, fishing, milling and smuggling.
It also shows how the river has inspired the work of artists, writers and musicians.
Scientists and politicians forecast the future of the river and describe what they call a "battle to safeguard the river's renowned but threatened tranquillity".
Mr McCarthy, who used to live in Woodbridge, said: "I lived beside and sailed on the Deben for many years and loved it for all its tranquil beauty.
"But I'd never appreciated the hidden depths, historical and natural that we've discovered making the film. It's even more magical a place than I'd ever imagined."
The film has been made in association with the Woodbridge Riverside Trust (WRT).
All five showings of the film at the Riverside Cinema have sold out.
The film's producer and WRT trustee Malcolm Hodd said: "We believe this is the most comprehensive review of the whole river Deben ever made, a call to protect this amazing asset for future generations."