Wings of Desire, 1987. Full Movie Thumbnail Grid.

Wing of Desire thumbnails.
Complete two hour movie in thumbnails.
./ffmpeg -ss 00:00:05 -i "Wings of Desire [1987].mkv" -frames 1 -vf "select=not(mod(n\,60)),scale=200:125,tile=59x34:padding=1:color=green" -vsync 0 22out.png

The above command was not used to generate the thumbnails, but it is one tried and including here for a reference point, but future attempts require trial and error.