Well now, this is lovely. Juliana Strangelove (a contralto) and Artur Vasiliev (a countertenor) sing Nick Cave’s ‘Where the Wild Roses Grow’ as a duet. This may make your brain go a bit weird, particularly at the start. It’s something of a musical McGurk Effect, with a dusting of pre-conception concerning what we think male and female voices sound like added to the mix.
They are lipsynching in this video, which only adds to the oddness, but in case you think they can’t do what they appear to be doing, there is this video where they perform the same song, live, though the sound quality is poor.