What is the test for overturning a finding of guilt beyond a reasonable doubt?

Indeed, "it is the jury, not the appellate court which must be convinced of the defendant's guilt beyond a reasonable doubt. '"If the circumstances reasonably justify the trier of fact's findings, the opinion of the reviewing court that the circumstances might also be reasonably reconciled with a contrary finding does not warrant a reversal of the judgment."'" (People v. Bean (1988) 46 Cal.3d 919, 932-933.)