For the 20th Anniversary of Greubel Forsey, the brand is back with their 10th "Fundamental Invention:" the Nano Foudroyante EWT, and it's a doozy of a watch. If you know the brand, you'll know their inventions, and the "Invention Pieces" that have celebrated these achievements have often iterated on the tourbillon, and this is no exception. What all started with the 30º double tourbillon led us to this: an incredibly wearable monopusher chronograph (a flyback, no less, and their first chronograph) and their first-ever flying tourbillon. But that's not all that's going on here.

This watch, in a 37.9mm by 10.49mm white gold case with tantalum bezel and display caseback ring, also features a constantly-running seconde foudroyante (or lightning seconds) that subdivides each second into six parts based on the 3Hz tourbillon cage. It's also directly tied to the tourbillon, sitting on top of the case that rotates once every 60 seconds while maintaining a vertical orientation. By tying directly to the oscillations of the tourbillon, Greubel Forsey has eliminated the number of extra components for the normal foudroyante drive train, keeping the movement small (31mm in diameter) and relatively low on parts (428 total).

Of course, there are limitations. The watch has a 24-hour power reserve with the chronograph running (they haven't shared the total power reserve without the chronograph activated). The other limitation, no pun intended, is that the incredibly expensive CHF 465,000 Nano Foudroyante EWT will only be made in 11 pieces. However, each piece will get all the hand-finishing that Greubel Forsey has been known for among collectors for a long time.

Money and access being no option, this watch is in my top three pieces I'd buy that came out this year. It might even be the first place I plop down an imaginary credit card, sweating with excitement about feeling like I'd robbed a bank and got away with something incredible (and no, not the one I'd have to rob to afford this watch). 

Let's put the price aside for a second. If you know the Vince McMahon meme, I think it perfectly describes the reactions I got when I described this watch to my colleagues. Only 37.9mm wide? You have my attention on that alone. Just 10.49mm thick? I think I like it. Monopusher chronograph? Sign me up. With a flying tourbillon and seconde foudroyante direct to the tourbillon cage? What are we even talking about anymore? This is nutty.

As I mentioned, the size alone is remarkable. I will say that despite being only 10.49mm thick, it does sit a bit high on the wrist because of the lug placement, shape, and length. The tantalum case back ring and sapphire caseback add dimension to the back that lifts it off the wrist, and the tantalum bezel and domed front crystal also add to the depth. While it's slightly more modern width-wise, it kind of reminds me of a Patek ref. 5004 (12.8 mm thick) in the way that it just sits higher on the wrist. But I'd take both all day, every day.

When I told Ben Clymer about this watch, he told me this is the kind of thing that watch lovers, and, specifically, the target market of Greubel Forsey, would have gone crazy over 10 years ago. Since then, I think Greubel has slightly fallen off the radar. I mean, we are talking about an approximately $540,000 watch, so the number of clients is pretty narrow, but there are more people out there buying at that level than you think. Yet, in two years of traveling the world to high-end collectors' gatherings, I've only ever seen two Greubel Forseys worn on the wrist, and both were at IAMWATCH in Singapore earlier this month. What happened?

Greubel Forsey has struggled to find itself the past few years amidst a world where hype has driven buyers to more prominent names. They've also rapidly expanded, doubling the 130 pieces/year in 2021 to 260 just a year later in 2022. They also (seemingly briefly) attempted to move "downmarket" with some simpler releases, but even those were ridiculously complicated and in the six figures. Plus, there are two distinct design languages within Greubel Forsey. 

While the Convexe line might attract more modern buyers, it butts up against Richard Mille, which (quality and watchmaking aside) scratches the same itch at a similar price but is easier to get (a funny thing to say about a hard-to-get watch but still) with 5,600+ pieces made a year. But this – this is exactly what Greubel Forsey needs right now. It's also – as I've said – absolutely outrageous in all respects.

I won't get deep into Greubel's "nanomechanics" and "nanojoule-scale" energy management. There's just not enough information for me to understand if that's true or just marketing speak. I think it's maybe worth a follow-up with Stephen Forsey to better understand this all (we'll see if we can make this happen). 

But even the singular achievement of a seconde–foudroyante (one of my favorite complications) that splits each second into six parts driven directly by the 3 Hz balance wheel – that's pretty fantastic. According to GF, a traditional foudroyante consumes 30μJ (microjoules) per jump, while the Nano Foudroyante uses only 16nJ (nanojoules) per jump, representing a massive leap in efficiency. 

In quintessential GF form, every part of the new Nano Foudroyante EWT movement is immaculately finished, from the column wheel for the chronograph to the extensive mix of frosting, mirror-polishing, and chamfering. At first, I thought the location and size of the bridges distracted from what you'd normally want to see from a chronograph – the mass of gears and levers that make it all work – but over time; I realized that this is gorgeous in its simplicity.

I also can say that, while this is probably the most complicated watch Greubel Forsey has been sitting on, it's not the only one that will excite brand fans. There's more to come. Yes, this is all outrageously expensive, but there will be 11 people out there who will get one of the coolest and most impressive watches I've seen this year.

Greubel Forsey Nano Foudroyante EWT; 37.9mm diameter by 10.49mm thick white gold case with tantalum bezel and caseback ring; 30m water resistance. Multi-level dial in gold, rhodium-colored, engraved and black lacquered hour-ring and minute-circle with a visual opening for the tourbillon, small seconds and chronograph minutes counter in gold, polished bevel; Foudroyante, frosted, fractions of seconds engraved and black lacquered; Hours, minutes, lightning seconds tied to a flying one-minute tourbillon, monopusher chronograph. Hand-wound movement running at 3 Hz with 24 hours of power reserve with the chronograph running. Non-animal material, hand-sewn strap; White gold pin buckle, hand-engraved GF logo; Price: CHF 465,000 (Approximately $540,000 at time of publication). Limited to 11 pieces