The Salt Path, an unexpected best-selling book by Raynor Wynn, tells the life-affirming story of a couple who lose their business, are made homeless and face terminal illness (in the case of her husband Moth) and decide to embark on the epic 630-mile South West Coast Path with barely the clothes on their back.

They rely on the kindness of strangers for survival and learn to live with nature on the length of their trek from Minehead to Poole, with plenty of tears, laughter, sheer endurance and a real feeling of place – the sea, cliffs, coves, rocks, wildlife – as the determined couple deal with everything thrown at them.

The uplifting tale came to the attention of the Gigspanner Big Band who were inspired to research songs originating from the areas the path crosses – Somerset, Devon, Cornwall and Dorset – and, not unnaturally, unearthed a reach seam of material.

From there it was just a short hop to develop show combining the words of Raynor, now an ambassador for the path, with some of these traditional old songs and tunes. Thus, Saltlines was born and here at Lighthouse was, appropriately, the final night of an eight-date initial tour loosely following the route of the path.

All good so far. However, what I, and perhaps others didn’t realise (and that’s probably my own fault) was that Wynn would not actually be talking about the book, the couple’s heart-wrenching experiences and ultimate salvation and offering plenty of insights behind the writing of it (and its lesser sequel The Wild Silence) in the usual book tour way.

What we actually got was performance art – Wynn’s narration of her own flowery poetry-prose from stage left interspersed by stunning musical interludes from the brilliant Gigspanner Big Band – with no communication or engagement with the audience until the usual thanks were given after the final tune.

It got a semi standing ovation so who am I to quibble about a beautifully composed evening celebrating the coastline in songs and words, but it could have been so much more. We didn’t learn what any of the songs were called, their backgrounds and who performed them, which is pretty much a folk tradition. More’s the pity.

Gigspanner is a trio comprising Steeleye Span founder member and fiddler extraordinaire Peter Knight, guitarist Roger Flack and percussionist Sacha Trochet. For the big band they are augmented by the incomparable Philip Henry on dobro/harmonica and Hannah Martin on vocals, violin and banjo (better known as Edgelarks) and go-to melodeon wizard John Spiers, of Bellowhead fame.

They are, of course, sublime, working perfectly together, particularly when getting into a lengthy groove, but also during quieter moments when soporifically replicating the sea, or even a group of knitters. Six musicians on top of their game enjoying something new and approaching it with joy.