Musician and writer Karl Bartos has long been an admirer of Weimar-era culture. During his time in Kraftwerk, he helped create the stunning track "Metropolis," directly inspired by a band viewing of the classic 1927 Fritz Lang film of the same name.

The original orchestral music composed for The Cabinet of Dr. Caligari by Giuseppe Becce had long been lost and in 2005, after watching the film, Bartos imagined what it would be like to create an entirely new one in the 21st Century in his home studios in Hamburg.

Now with crystal clear images, digitally restored by the Friedrich-Wilhelm-Murnau-Foundation, the film is visually the best quality it has ever been. With Bartos' soundtrack, there is impressive sound to go with the haunting vision.

Narrative film music and sound design for Robert Wiene's classic 1920 psychological thriller. For the task, Bartos ransacked his own library of musical compositions, recreating pieces he had written as a young classical musician in his pre-Kraftwerk days whilst creating new sounds, melodies, and textures.

The intention was not simply to write a film score per se. This was to be an immersive listening experience with special sound effects to match the action as we enter the film as both spectator and participant.

By taking the characteristics of Expressionism in the arts and transferring them into film making, a disturbing, distorted depiction of reality enwrapped and entrapped the viewer. The subjective replaces the objective.

We are sucked into a parallel world lit in menacing chiaroscuro, where dimension, proportion, and perspective are all off skew. From the convex polygon-shaped windows of precipitously sharp-inclined buildings to the surreally odd tables and chairs with long spindly legs to be found in preposterously small and oddly shaped rooms, alienating camera angles and impossible vanishing points, the town of Holstenwall in which much of the action takes place is the world of the imagination, not the empirical world of our own eyes and ears.

All the time the listener is on a journey, sounds move in and out, music weaves and entwines, the soundscape is immersive and intoxicatingly rich. It is music which is, by turns, beautiful, amusing, playful, and profoundly disquieting and it is a perfect fit for the aesthetic of era-jumping in the actual film.

'There's something about this film. No matter how often you watch it, it keeps its secrets. Who is mad and who is not always remains a question of interpretation,' says Bartos. The film remains an enigma, but now one with the soundtrack and soundscape it deserves.