I think this will get more response in the Wristwatch Forum.
It has been quite a while since I have paid much attention to wristwatches, but I recall that during the "bad days" of the 50's and 60's many Swiss makers were selling low quality pieces to compete in a declining market.
@Kinpol, who do you think actually made the watch? Is it a Chinese forgery?
Looks like a nice vintage Ulysse Nardin. In the picture, the second hand looks a little short. That could just be the curve of the crystal or a replacement hand. The movement looks like what you would expect.
Case and movement look genuine to me. This looks to be a US market watch. It has a three-letter import mark near the balance which cannot be read in the photo provided. One should be able to trace the US importer to confirm that the movement is legitimate.
Dial may be a older redial which has not aged well. An original dial would likely have "Swiss" or "Swiss Made" at the bottom.
An interesting watch, but not necessarily a valuable one.