Still, it must have been disconcerting, watching someone play yourself? 'Yves is a very well-known impersonator on Canadian television so I was expecting a certain likeness,' says Lepage.
Jacques remembers the first time Lepage saw the show. 'It forced Robert to take a step back as a director,' he says. 'It almost became a new work for him and helped him to go further with the show.'
Lepage started crafting his radical style in Quebec in the late 1980s, breaking with convention by prioritising the visual image over the spoken word - partly as a response to living in a country divided by two languages. He's no stranger to the risks of working in free-form: 'The first rule of directing is to know where you are going,' he says. 'But I never have any idea.'
Both Lepage and Jacques agree, however, that The Far Side Of The Moon's own unequivocal success lies in the way it combines a very local story (Lepage's own) with something universal (mankind's restless desire to know what lies beyond).
Clearly it has evolved since London audiences saw it two years ago, but that is all part of the fluid beauty of Lepage's theatre pieces which, by definition, are in a constant state of flux.
Lepage has recently been working on a film version of the show, which he says he's happy with. But you'd be a fool to forgo the live thing for the celluloid version: it really is a very special theatrical experience indeed.
The Far Side Of The Moon, Thu until Oct 25, Barbican, Silk Street EC2, Thu 7pm, otherwise Mon to Sat 7.45pm, £10 to £30. Tel: 0845 120 7550. www.barbican.org.uk Tube: Barbican/Moorgate