Boris Godunov represents Mussorgsky's attempt to blend a distinctive Russian vocal style with romantic lyricism. To this end, he used modal harmonies and rhythms typical of folk music and of sacred hymns of the Orthodox Church: naked, unpretentious melodies and unusual orchestration. The result was an opera so radical that, when the composer presented it to Imperial Theatres in 1869, it was brutally rejected. A plethora of revised versions followed, some by Mussorgsky himself, some by fellow composers – notably, Rimsky-Korsakov and Shostakovich – which resulted in an exceedingly complex and intricate creative history and an abundance of alternative material.

Kent Nagano has decided to go straight to the source and put together a concert production of the very first 1869 version (with a few cuts). The original orchestration has been described by critics as "raw" and "dark", but this is precisely what makes this version so powerful. The Polish act and the folk songs, which were added in the first revision and often performed even in modern times, are thoroughly entertaining, but their absence focuses the drama on the main character. The result is a gloomy, more intense atmosphere. The work, as envisioned by Mussorgsky in his first composition, is relentless in pursuing Boris' psychological evolution and descent into madness.

The plot is set in the politically chaotic era in Russia between 1598 and 1605, the so-called "Times of Trouble". Boris is unanimously elected Tsar, but he is responsible for the murder of the legitimate heir to Ivan the Terrible's throne, the Tsarevitch Dmitri, who was only 7-years old. The guilt gnaws at Boris' body and soul: he has absolute power, but famine ravishes the land, and his own people hate him. He feels like an usurper, illegitimate and alone. The plot develops in a seven scenes, from the coronation to the Tsar's death.

The Gothenburg Symphony Orchestra, under Nagano's precise direction, managed to bring out all the colours that Mussorgsky used to paint the scenes of the opera. Each scene is a story unto itself, with characters that often do not appear in other scenes, the composer giving each scene its own atmosphere, using the instruments and the rhythms in different ways. The orchestra and Nagano did a marvellous job of interpreting this unique style without shying away from the roughness that Mussorgsky skilfully uses to convey strong emotions. Nagano successfully held the ensemble together with extreme precision, and this helped to efficiently convey his vision of the score: a unified view of Boris' psychology, expressed by distinct and contrasting moods and impressions in the different scenes.

The Göteborg Opera Chorus was undoubtedly one of the stars of the evening. The chorus is one of the protagonists of Boris Godunov: it is the voice of Russia itself and the physical embodiment of his own conscience. The choir projected an impressive amount of sound with amazing incisiveness. The Coronation Scene was remarkable: orchestra and chorus at full throttle and the cathedral bells in the Konserthus hallway heard from a slightly open door contributed to a sense of majesty and momentous occasion. Boris' gloomy musings clashed against this golden canopy of sound with intensity.

Alexander Tsymbalyuk was a commanding, if perhaps young, Boris. His bass was extremely warm and beautiful, but the most impressive quality of his voice was how natural it sounded. His technique is solid, and he sounded like a professional actor performing in a play, all the nuances of the speaking voice finding their way into his singing. The monologue of the fifth scene was heart breaking, even more so than his death scene.

His nemesis, the monk Pimen, was portrayed by another young bass, the Finnish singer Mika Kares, whose low notes featured the earthy, deep timbre one associates with Russian voices. He left me with the desire to hear him in the title role.

A third bass in the cast, Oleg Budaratsky, was also quite young and had a robust and well set voice, which gave a distinctive personality to the minor characters of the police officers in the first scene and in the inn scene, making them stand out in spite of their small roles.

Boris Stepanov was remarkable as The Simpleton, in what is perhaps the most interesting scene of the opera. Tsar Boris faces the hungry, furious crowd in the cathedral square (wonderfully portrayed by the chorus), and a "Holy Fool" openly accuses him of the crime of killing young Dmitri. Boris, rather than having him arrested, asks him to pray for him, and The Simpleton refuses, leaving the Tsar crushed by his conscience and unable to respond. It's the beginning of the end.