At an event to publicise his autobiography, Unterweger aka Malkovich rants and raves about women, liars, his editor and the evening's pitiful organisation, regularly interrupted by sopranos Laura Aikin and Aleksandra Zamojska, interpreting arias by Vivaldi, Mozart, Beethoven or Haydn.
More than a play about his life, the piece is an angered monologue by an egomaniac, a narcissistic Don Juan who adores and at the same time despises women, in turn caressing and strangling his two singing co-stars.
"I'd rather be a killer than a no one," says Malkovich's character, hinting at the motives behind his crimes.
Speaking from beyond the grave -- he committed suicide in prison in 1994 -- Unterweger teases the audience throughout the almost two-hour piece, promising to reveal his deepest secrets but remorseless until the end.
First jailed in 1974 for murder, Unterweger became a minor celebrity after writing a successful autobiography and several plays in prison, securing his early release and going on to work as a journalist.
He is believed however to have committed further murders in the Czech Republic and California, and was finally re-arrested in Miami.
Created by the Austrian team of Michael Sturminger, Martin Haselboeck and Birgit Hutter, "The Infernal Comedy," which runs until Sunday, premiered in 2006 in Los Angeles, also with Malkovich in the main role.
Throughout the piece, operatic interludes are provided by Aikin and Zamojska, representing the women in Unterweger's life, from his mother to his lovers and victims.
Interrupting his monologue on another occasion, Malkovich petulantly orders the orchestra to entertain the audience while he takes a break.
The fragmented result is neither an opera nor a straight play and performed in English moreover, this is an unusual piece for Vienna.
But the final applause makes it clear: the main attraction is seeing Malkovich on stage.
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