Revisiting the sci-fi vibe of MB&F’s earlier Horological Machines, HM12 The Guardian is a mechanical duo combining the highly complex HM12 wristwatch – featuring a novel “face shield” complication, a flying tourbillon, a double-sided micro-rotor, jumping hours and traditional fine finishing – with ‘The Guardian’, a towering 38cm-tall robot equipped with a mechanical thermometer and integrated tools. Each combined unit comprises nearly 1,500 components. Only three limited editions of 12 pieces will ever be crafted.
The mind within the Machine
The robots of founder Maximilian Büsser’s childhood have influenced MB&F’s creations from the beginning. One of the most striking examples came in 2015, when MB&F partnered with L’Epée 1839 to create Melchior, a robot-clock shaped by Büsser’s memories of toys, science fiction and machines imagined as personalities rather than objects. In 2026, MB&F introduces something new: a wristwatch conceived as the brain of a robot; and a robot that gives the wristwatch a presence far beyond the wrist.
A total horological concept to open the third decade
Originally imagined to celebrate MB&F’s 20th anniversary, the development of HM12 The Guardian took far longer than expected. The project expanded and became more complex. What first seemed like a delay gradually revealed itself as an opportunity: it became the perfect object to launch the brand’s third decade.
HM12 The Guardian is not a watch; it is a complete horological concept – and a deliberate return to MB&F’s roots, at a time when much of the brand’s audience has discovered it only recently. HM12 arrives as a recalibration. A way « to put the church back at the centre of the village » as we say in French.
Back to the Idea
At MB&F, going back to the roots does not mean revisiting the past. It means returning to the ideas and principles that have shaped the brand from the beginning, and testing whether they still hold when pushed forward. One of those principles has always been: a creative adult is a child who survived.
HM12 The Guardian revisits key elements developed over the past twenty years and recombines them into a single object. Part Horological Machine, part Legacy Machine, part Co-Creation, it brings together narrative design, high-end watchmaking, mechanical experimentation and a playful relationship with the object.
A new creative duo
HM12 also marks a pivotal moment in MB&F’s creative structure. For the first time, after 20 years of collaboration with renowned designer Eric Giroud – who remains a key partner on other projects – an Horological Machine is conceived and developed entirely by the tandem formed by Maximilian Büsser and Maximilian Maertens. Max and Max have been collaborating for several years, but until now Maertens’ work had been mainly visible in the clocks and music boxes co-created by MB&F with L’Epée and Reuge.
Büsser provided the initial impulse for HM12 The Guardian, framing the concept: What if a robot’s head were a watch? He then stepped back and Maertens became the architect and guardian of the project. Over four years, Maertens iterated relentlessly: drawing, modelling in 3D, printing prototypes, testing stability and adjusting proportions.
A face, before a watch
Visually, HM12 is frontal. It reads immediately as a face, the head of the robot it sits on. Two eyes. A presence. The references are layered. For Max Büsser, they stem from early memories of robots and toys, from the science fiction imagery of the 1970s and 1980s, when machines were imagined as characters, explorers, or guardians. For Max Maertens, they come from a later generation, shaped by Transformers, animated series, and films like I, Robot, where robots evolve, adapt, and take on more complex roles. HM12 sits at the intersection of these imaginations across different eras.
A mechanical face
Developed entirely in house, HM12 is the result of a movement and case architecture that took more than four years to complete. Every element was designed internally, with narrative intent and mechanical constraints addressed simultaneously.
HM12 is conceived as a face, the entire watch forming the robot’s head. The time display occupies the position of the eyes. Instantaneous jumping hours on the left and trailing minutes on the right are read at a fixed point, while the information moves on rotating discs.
Below, one side of the micro-rotor – shaped like the MB&F battle-axe – sits where the mouth would be. Above, the flying tourbillon functions as the brain, deliberately exposed, with a classical aesthetic grounded in high-end watchmaking rather than futuristic design. The skull of HM12 is largely made of sapphire, allowing light to enter from multiple angles and strike the tourbillon directly, visible from the front and laterally through the side of the case.
The face shield, a mechanism within the mechanism
One of HM12’s defining features is its face shield system, treated as both a complication and a functional element tied to the object’s narrative. Within the logic of the watch, the shields exist to protect the robot’s face. They also radically transform and bring colour to the face of the watch.
Actuated via the left crown, the shields move in a continuous, linear way. The wearer controls how exposed the face remains and can stop at any point, from fully visible to concealed. The crown is declutching: once the shields reach their stop, it disengages.
The system is entirely mechanical and fully independent from the movement. More than 200 components are dedicated to this function alone, a level of complexity that exceeds that of many complete mechanical watches. Chatons, polished wheels and inward angles demonstrate a level of finishing usually reserved for traditional horology.
Development was handled in parallel, one engineer focusing on the timekeeping movement and the other on the shield system, while maintaining constant alignment to prevent conflicts in space, kinematics, and function. The result is a single machine in which mechanics and narrative are developed together.
The other side of the head
Developed entirely in house, the HM12 calibre has a power reserve of 84 hours and comprises 646 components – most of which are hand-finished – including 86 jewels. From the back, HM12 reveals a different register: this side follows a more classical, traditionally horological language. Where the front leans toward a futuristic expression, the back is restrained. The calibre was shaped to follow the case, not the other way around. Echoing the proportions of a human face, the movement is open, balanced and symmetrical.
The finishing reinforces this contrast. Bridges are softly curved and hand finished, with a grained surface on the mainplate. The rear rotor features a guilloché dome executed with the involvement of renowned independent watchmaker Kari Voutilainen and his team, a demanding exercise given that the guillochage is applied to a curved, spherical surface rather than a flat plane.
HM12 sits deliberately between two worlds, combining the expressive futuristic language of the Horological Machines with the classical refinement of the Legacy Machines.
The Guardian, a companion, not a stand
HM12 is delivered with The Guardian, the rest of the robot’s body – the two are one. The watch detaches from its strap via a quick-release system and mounts directly onto the head via a clipping system designed to secure it firmly while allowing repeated handling. The strap is stored in a hidden drawer integrated into the robot’s base. This is not a base or a stand. It is a body built around the watch.
The development of The Guardian was entrusted to L’Epée, a long-standing partner of MB&F. The robot is conceived as a mechanical extension of the watch and includes 755 components. At the centre of its chest sits a mechanical thermometer, acting as the heart of the robot. Each arm carries a tool. On one side, a shield that contains a loupe, calibrated to inspect the movement and reveal its finer details. On the other, a detachable torch with UV capability, designed to activate the Super LumiNova on both the watch and the robot itself.
A one-time object opening to the future
HM12 The Guardian is produced in three limited editions: blue, purple, or green. Only twelve pieces per colour, for a total of thirty-six. No more.
HM12 The Guardian brings together many of the elements that have shaped MB&F over the past twenty years: a sci-fi inspired Horological Machine, an entirely in-house calibre, traditional high-end finishing, an unconventional display, and a mechanical companion designed to be handled and explored. What first appears as a playful sculpture is in fact the result of years of development and nearly 1,500 components working as one.
HM12 The Guardian revisits MB&F’s roots – creating mechanical objects with strong personalities, real technical substance and a sense of wonder. It reaffirms those foundations and carries them into the brand’s third decade.
