Documentary following the inspirational Orchestre Symphonique Kimbanguiste and choir as they make their debut visit to the UK. It captures the latest step in an extraordinary odyssey for the world's first all-black orchestra, formed 20 years ago from a group of self-taught church musicians in Kinshasa, the capital city of the turbulent DRC. From the moment the 100-strong party led by conductor Armand Diangienda touches down at Manchester Airport, we follow them night and day as they work side by side with the Halle orchestra and choir and later at the Southbank in London with members of the National Youth Orchestra, BBC orchestras, Southbank Sinfonia and more. Amongst the hectic schedule of instrument repairs, seminars, rehearsals and performances, they still find time for a visit to Manchester United's Old Trafford ground, and down south take a trip to the Proms and a flight on the London Eye that turns into a joyous spontaneous singalong. The climax is a concert at London's Royal Festival Hall, with a programme embracing the rousing ode to brotherhood of Beethoven's 9th, along with a symphony written by members of the orchestra. From the inside out, Congo Calling charts the pride and the passion - and the joie de vivre - of an orchestral community abroad. It is an eye-opening exchange of experience and ideas between European and African musicians, between seasoned professionals and ever-passionate amateurs.