When it was introduced in 1994 the Gérald Genta Grand Sonnerie was the most complicated wristwatch in the world. With its characteristic pyramidal stacked case design and immensely complicated Cal. 31000 – composed of more than 1000 parts in variants like this particular lot with retrograde date indicator – there was nothing quite like this wristwatch in the 1990s. The development of the movement was led by Pierre-Michel Golay the brand’s technical director and co-founder who would later go on to work for Franck Muller.