1. Does it have at least two women in it,
2. Who [at some point] talk to each other,
3. About something besides a man.
I bring this up as a point of interest, because of what it says about the blind spots of popular entertainment. Most Hollywood movies fail this test; if you extend #3 only slightly, to read "About something besides men or marriage or babies", you can strike out about 50% of the small proportion of mass-entertainment movies that do otherwise seem to pass the test.
The reason Bechdel's test is important is because it's a diagnostic indicator for the objectification of women. It's designed to identify the kind of film where, if two women talk to each other at all, the only subject of conversation is men (or babies). What it tells us is that our current movie and (to a lesser extent) our TV culture is pathologically misogynistic — be it in in the adoption of conservative Kinder, Kuche, Kirche values or the more extreme violence of women in refrigerators.