Help me remember the title of a movie

All i remember about this movie is that a couple are scientists together, the wife gifts her husband a watch. One day at work he forgets his watch inside the machine they were building and testing so he goes inside to get it, the door closes trapping him inside, it turns on and he yells for help. His wife and fellow scientist friends come to help trying to open the door but they cant and he dies or disapears (vanishes or becomes invisible), i dont remember. I also dont remember if the only thing left is the watch or if all of him is gone.

That is the creation of Dr Manhattan in Watchmen:

YES YES YES. Last night when I was trying to figure out the movie I was thinking it was similar to the Fantastic 4 but it couldnt be, then i thought of Watchmen but decided it wasnt because i dont remember seeing it there but now that you mention it, yes. Thank You @Stonebroke