'Scottish Mussel' is a British comedy based on a Scottish chancer, called Ritchie, with no real prospects who decides to start working at a Highland conservation centre as an illegal pearl fisher. Here, he meets Beth, a pretty English girl who is passionate about saving endangered mussels in the Scottish Highlands. He instantly falls for her, but must beat off competition from a smooth American worker as well as an old school friend who tries his hand at pearl fishing due to its success. Ritchie must start to question his own motivations, whilst trying to save the Highlands from ecological disaster and win Beth's heart.