Welcome, Gwandad.
To make sure filters are not causing this, select
Filters>Reset filters. Also, make sure there is no search active. If there is, there will be a clear button to the right of the search box. Otherwise, I'm not sure what you mean. If you can "double-click it in the database," then obviously "it" is still there. But I have no idea what you mean by "it opens up a new PVD screen." Before you double-click, what does appear in the information panel on the right? If it's some other movie, that's probably because that movie is selected in the list, rather than the one you think is selected.
On the other hand, if you see nothing (i.e., the information panel is empty)—even though a movie is selected in the list—that might suggest a problem with the skin (although I've never such a problem). Double-clicking on an movie in the list puts the record in "edit mode." That results in all the fields being shown, whether on not they have any data. So double-clicking can result in you seeing something that wasn't there before. Try changing the skin at
Preferences>Appearances>Movie information skin—just to see if that makes any difference. Also check
Preferences>Movies>Visible items and make sure all fields are checked.
If I haven't tripped over your problem yet, but maybe this will help you better describe what's happening.