A thriller in black and white is not automatically film noir

If there is one thing film buffs agree on, it's that there is no fixed definition of what film noir is or isn't.

*MY* definition is:

(a) a crime must be a key plot point (sometimes just as a MacGuffin to move characters into interaction)
(b) moral ambiguity on the part of one or more characters

and, optionally

(c) a semi-fatalistic point of view (we're all at the mercy of random forces in the universe)

Femme Fatale's are nice, but not necessary.

B&W cinematography is typical of film noir, but also not necessary (see 1955's "Violent Saturday", an excellent noir shot in widescreen color). B&W was used mostly just for economic reasons until 1954, which was the tipping point year when more & more movies had to go widescreen color to compete with TV (after 3D failed in 1953).

"Pushover" qualifies as film noir by my criterion. It's not in my top 25 noirs, but it's better than most.

The 3 essential features of film noir:

1) It must involve a crime.

2) It must take place in a working class or middle class milieu.

And --

3) The main character must make a poor and reckless decision in the early going (usually to commit an immoral act) -- for love, or money, or both -- that seals his fate, and (often) leads to his destruction.

Thus, BODY HEAT is a film noir, while CHINATOWN, for all its brilliance, is not.

...And PUSHOVER definitely is.