The men wearing hooded tops who walked into ROX on George Street in Edinburgh at 5.15pm on Monday may have been targeting the rare time-piece from Swiss brand Girard-Perregaux which is worth £500,000, but it was not in the shop at the time.
The raiders did take other watches of the same brand as well as numerous diamond rings and necklaces.
The showpiece watch was unveiled amid a blaze of publicity at the store which was opened in October by television personality Cat Cubie and rap artist Labrinth.
One man had an axe while the other was carrying what looked like a dark-coloured handgun. They began the heist by using the axe to smash the glass display cases before a shop assistant was grabbed and forced to open a window display.
Police said the robbery was a "terrifying ordeal" for the two female staff, who were unhurt. The raiders left with the haul of jewellery and made their get-away wearing red and white helmets on a black Honda 650 motorbike which was later found abandoned less than a mile away in Northumberland Street Lane North.
The axe has also been found and sent for forensic analysis.
A ROX spokesman said: "This has been a terrible ordeal for our staff. Their safety is our main priority at all times and we are thankful that although they are badly shaken, no-one was physically harmed.
"Initial estimates suggest £1m worth of stock has been taken including diamond necklaces and engagements rings worth upwards of £100,000 each and luxury watches from brands including Hublot and Corum.
"Girard-Perregaux watches were also taken during the raid. However, the rare Opera 2 timepiece worth £500,000 has not been in the store since Christmas."
Officers are now keen to speak with anyone who remembers seeing any suspicious activity in either George Street or Northumberland Street North West Lane on Monday evening.
High-visibility police patrols have been deployed in the area to reassure residents and firms.
The axeman is described as wearing a dark-coloured top and jogging bottoms with a stripe down the sleeve and leg. The other man is described as wearing a dark top and dark jogging type trousers.
Witnesses describe one of the men speaking with an English accent, while the other is described as having a local accent.
Detective Chief Inspector Bobby Deas said: "We are conducting various lines of inquiry to trace these items and identify those responsible for the theft.
"The motorcycle, which was used during the suspects' get-away, is believed to have made a lot of noise as it sped off and members of the public who were nearby would have heard it.
"We would now urge anyone who remembers seeing or hearing the bike, or who recognises the description of the riders to contact police immediately.
"Similarly, anyone with any other information that can assist with our inquiries is also asked to come forward."