If you thought the definitive solution of how to perform Berg’s unfinished opera Lulu had been found when Pierre Boulez first conducted Friedrich Cerha’s completion of the work in the late 1970s, think again. Confidence in that version seems to be waning. A few years ago Welsh National Opera tried out an alternative completion and there are still companies prepared to stage nothing but the finished first two acts and maybe the Lulu Suite that the composer put together shortly before his death. Hamburg State Opera has come up with an intriguing third way, neither a completion nor exactly a torso – indeed, it runs longer than most stagings, to over four hours.

The team of conductors Kent Nagano and Johannes Harneit, director Christoph Marthaler and dramaturge Malte Ubenauf have gone back to what Berg left in his manuscript of Act III – a so-called short score in the form of one or two keyboard parts and the occasional line for a solo violin. And this is how the two scenes of the act were performed here. PC (Performance Correctness) gawn mad, one could argue, but it was surprisingly effective. In trying to negotiate the programme articles it is never quite explained why the team has rejected the 300 or so bars of the first scene that Berg did complete and orchestrate, and we thus lose the scene with the Jungfrau shares, but they are adamant that the assumption that the Adagio from the Lulu Suite was to form the interlude between the act’s two scenes is “pure speculation” and so, sadly, dispensed with. The gain, though, is that as Countess Geschwitz mourns over Lulu’s lifeless body, her words “Lulu, my angel” herald an epilogue in a performance of the complete Violin Concerto, the work that Berg effectively abandoned Lulu to compose and famously written ‘In Memory of an Angel’, Manon Gropius. Played here with great poise and emotion by Veronika Eberle, who had already appeared as an on-stage violinist at the beginning of the act, the effect was cathartic in coming to terms with the whole evening’s drama.

And that drama itself had been of a certain detached nature. The experimental Swiss theatrical director Marthaler, whose work in opera has so far been fairly limited, though including a production of Tristan at Bayreuth a decade ago, takes a non-naturalistic approach here. Spoken dialogue is deliberately stilted, characters often converse without physically interacting and movement is sometimes perversely repetitive. As if to emphasise this enigmatic approach, Lulu’s portrait is a painting of her dressing-gowned figure curled into the foetal position and seen from behind – a symbol, perhaps, of her essential loneliness.

There are also four extra women, named in the cast list for characters from Wedekind’s original plays, who seem to act as ‘other Lulus’ and who come together to perform strange routines, for instance in place of the usual central film interlude, and again during the concerto, where they are joined by a resurrected Lulu and, at the very end, Eberle. Like much of the direction, the stage action often seems confusing and inexplicable in itself, but yet seems subconsciously to work and to sit well with the text. (Speaking of the text, it is excellent to find Hamburg now offering English surtitles, though – and not wishing to look a gift horse in the mouth – it was a pity that in this case a singing translation was used, which entailed variances from the original in both meaning and some character and place names to fit the musical lines.)

It’s undoubtedly a highly physical production, built around the dramatic and talents of Barbara Hannigan in the title role. Her vocal assumption was remarkable enough, negotiating the part’s stratospheric highs while hanging upsidedown, or teasing out details of phrasing while being thrown about like a rag doll by one of her many admirers. But it was the total performance, the complete identification with her character that impressed most. By contrast, Anne Sofie von Otter – on searing vocal form – portrayed Countess Geschwitz with brooding intensity, a woman with a quiet obsession and constantly snatching sorrowful glances at the object of her infatuation. Jochen Schmeckenbecher occasionally allowed his vehemence to get in the way of tonal security, but it was a convincing assumption. Matthias Klink’s Alwa was also impressive and the now veteran Sergei Leiferkus was in good voice as Schigolch. The rest of the cast, though reduced in number from the completed versions of the opera, was exemplary in every way.

Finally, the Philharmonisches Staatsorchester Hamburg played like a dream under Nagano’s acute direction, with beautifully coloured woodwind and sleek strings, and while the loss of an orchestral third act had to be borne, the recompense of the concerto was ample reward.