I will concede that this may be the minority opinion here, but Veronica Lake?!?! I love "Blue Dahlia" as much as the next guy, but I think she was a terrible actress. Maybe not terrible capital "T," but I think a number of actresses could have done better than her particularly in that one. Hell, I don't even like her in "This Gun for Hire," which everyone seems to like, but to me the biggest sin is "I Married a Witch" as she actually had the benefit of a great director who couldn't get a decent performance out of her. "The Glass Key" was weak material, sure, but she made it worse. She's at least part of the reason the movie's been left behind.
Again, could COMPLETELY be in the minority here, but give me Lana Turner or Barbara Stanwyck any day.
As for Through the Cracks suggestions, how 'bout Lake's occasional co-star Brian Donlevy?? Or the man who directed a vastly superior Somerset Maugham adaptation to the Lake-starring "Hour Before Dawn" only two years later ("Razor's Edge"), Edmund Goulding? As for movies, how about "Lonely Are the Brave?"