Sunset Boulevard

Today I finished watching Sunset Boulevard (1950,NR). From Wikipedia:

It stars William Holden as down-on-his-luck screenwriter Joe Gillis, and Gloria Swanson as Norma Desmond, a faded movie star who entraps the unsuspecting Gillis into her fantasy world in which she dreams of making a triumphant return to the screen.

I was enjoying it quite a bit as the plot thickened but then felt like it lost all of its steam at the end, so I give it 3 out of 5.