“I really enjoyed the technical challenges involved in the Chapter Three project,” explains Andreas Strehler. “Kari developed the majority of the movement architecture so I was able to concentrate on inventing an innovative ‘reveal’ opening/closing mechanism, conical gearing for the rollers, and maximizing production efficiency.”

Developing the movement from scratch enabled the rollers to be integrated to the caliber rather than added as a more space-consuming module. High-efficiency conical gearing—a Strehler specialty—contributes to both the efficacy of the power distribution and reliability of the mechanisms. The bespoke movement architecture also incorporates the mechanism for opening and closing the reveal panels in the dial. Building this functionality into the movement rather than adding to the complexity of the case maximizes both reliability and use of space. The panel open/close mechanism is a movement complication in itself. With the dial closed, pushing the button in the crown lowers the panels below the dial, and releasing the button causes them to rotate out of view so that the second time zone and day/night rollers are revealed. Pushing the button again rotates the panels into position and, releasing the button causes them to elevate and sit flush with the dial.

As might be expected from two of the world’s best watchmakers, rich functionality and stylish good looks were not enough: a superlative watch should also be an accurate timekeeper. To that end, the movement is regulated by a Straumann escapement, featuring a lightweight energy-efficient escape lever and balance spring with an isochronism-improving Breguet overcoil.

With Chapter Three ‘Reveal’ by Kari Voutilainen and Andreas Strehler for Maîtres du Temps, when it comes to choosing between functionality and style ... you don’t have to.