Since 2015, we have been filming some of the world's greatest classical musicians behind the scenes. And sharing them with the world.

Standing in the back of Henry Wood Hall in 2015, I knew we were about to witness something special. Steven Isserliss had just agreed to let me film a few moments of him playing through Imogen Holst's The Fall of the Leaf after a gruelling 13-hour day of concertos. As the lights went down, leaving our recording equipment running and hiding in the shadows, we captured one of the most magical moments we could have imagined. This was the personal creative time of one of the great masters, and we were sharing in it.

This was the beginning of an idea to create a portrait project exploring the reality of the musical experience. With just a single hand-held camera, two microphones and a couple of spotlights we went about finding out how to be invisible as we filmed the world's greatest musicians creating their own private, creative experiences.

Two years in, Fly On The Wall has become a reality. Not quite documentary, not quite music-video we have developed a minimalist 'guerilla-portrait' format, an experiment in invisibly documenting over 50 world-class musicians at their most unguarded. We have build a small group of like-minded artists, passionate about sharing these moments. With around a million views to date, our films are a regular feature on Classic FM. And our albums have won awards and recommendations from The Sunday Times, Gramophone, BBC Music Magazine and more.

- Stewart