We did a picture thread on this subject a few years ago.
I have four favorite facial expressions:
The look of fear on Carlo's face when he realizes that Mike knows he fingered Sonny:
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The blank, almost expressionless, stare that Mike gives Barzini at Vito's funeral. You just KNOW Barzini is a dead man:
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Vito's pained face as he looks upon Sonny's dead body (as he mutters, "Look how they massacred my boy"). Brando at his best:
.
And my favorite "Godfather" look - Sollozzo's face when he tells Tom Hagen, "Let me worry about Luca" (already knowing that Luca Brasi was dead):
