Tenebrae is a giallo film from Dario Argento and you can check the trailer above. I still haven’t watched this movie because I got distracted by the watch less than 30 minutes in. But after ID-ing the watch it makes perfect sense. Peter Neal is an author who goes to visit Rome on a press tour. While he’s traveling he’s wearing a Rolex Pepsi GMT Master. Without further information it’s very difficult to tell which GMT it is.

A quick google search tells us that Tenebrae was filmed in May of 1982. This means we can rule out the GMT Master II which did not come out until 1983. Then we have to determine with GMT Master I this watch is and looking at my incredibly low quality photo of my screen, I believe that it has more pointed crown guards instead of rounded crown guards. This leads me to believe that this is the ref. 16750 GMT Master I.