Scottish Mussel: Pearl poaching inspires new Talulah Riley rom-com

Talulah Riley and Scottish Mussel co-star Martin Compston

A new romantic comedy involves one of Scotland's most notorious forms of wildlife crime - freshwater pearl mussel poaching. Scottish Mussel's writer, director and star Talulah Riley hopes the movie draws greater attention to the plight of one of the world's most endangered molluscs.

For her directorial debut, actress Riley plumbed new depths - the chilly, fast-flowing rivers of the Scottish Highlands.

Her film's story centres on the illegal harvesting of freshwater pearl mussels.

Scotland is one of the few places in the world where Magaritifera margaritifera continues to be under serious threat from poachers.

Hundreds of dead mussels, their shells broken open by people hoping to find a rare pearl, have been found in recent years on riverbanks in the Highlands and Western Isles.

Riley got the idea for the script from her crime writer father Doug Milburn.

"My dad is Scottish and he is always sending me stories about Scotland," she said.

"Years ago he sent me a story from a newspaper on freshwater pearl mussel poaching.

"In writing the script I did a lot of research on the internet, but also got help from Peter Cosgrove, who is an expert on freshwater pearl mussels. He also gave us some poached shells for use in the film."

What are freshwater pearl mussels?

Freshwater pearl mussels are a protected species

These molluscs are similar in shape to common marine mussels, but can grow to the size of your hand and live up to 130 years in fast-flowing rivers.

Early in their lifecycle they live harmlessly on the gills of young salmon and trout.

Loss of habitat and pollution are among the reasons for the dramatic decline in their numbers.

Scotland's Highlands and Islands are among Britain's last strongholds for the critically endangered species.

But Scotland is also unusual in being one of the few places where the mussels continue to be seriously threatened by illegal poaching, according to Scottish Natural Heritage.

Piles of broken mussel shells have been found in recent years on riverbanks after being poached by criminals trying to find their rare pearls.

In history, getting to the prized pearls was said to have been among the reasons for Julius Caesar's first Roman invasion of Britain in 55BC.

Modern day efforts to protect and conserve the mussels include 2009 police project Operation Caesar and Pearls in Peril.

Illegal poaching threatens populations of rare mussels

Riley hopes some of those in the film's audience will be surprised to learn there are pearl mussels in Scotland.

"Most people might associate pearls with oysters and more exotic places, and not the cold rivers of Scotland," she said.

"They are hugely important to ecosystems. A lot of attention is given to the ice caps and polar bears but mussels, like bees, need help and a greater awareness to their plight."

Riley, who appeared in Inception and Thor: The Dark World, co-stars with Joe Thomas, Martin Compston, Paul Brannigan, Rufus Hound and Harry Enfield.

Martin Compston, Joe Thomas and Paul Brannigan also star in Scottish Mussel

Filming was done in locations in Scotland in October last year.

Thomas, a star of The Inbetweeners TV series and films, is no stranger to Scotland, being a regular visitor to the Edinburgh Fringe. He has also visited Inverness and Skye, where Inbetweeners producer Chris Young is based.

"Thankfully we were filming too late in the year for midgies, but it was pretty much winter by the time we finished," said Thomas.

"During filming the wind blew down the changing area. It was like the scene from Jurassic Park where the walls and the ceiling fall down on a building. We were left exposed to the elements."

Thomas added: "Being in a film about molluscs wasn't on my list to be ticked off. But the script is intelligent with genuinely funny jokes.

"The mussels make it original. They were an added attraction to me."

Riley and Thomas will also be interviewed on The Janice Forsyth Show on BBC Radio Scotland on Tuesday between 14:00 and 16:00.

Scottish Mussel will be released in cinemas later this year.