Two of these mice , jittery janitor Bernard ( Bob Newhart ) and his co-agent , the elegant Miss Bianca ( Eva Gabor ) , set out to rescue Penny ( Michelle Stacy ) , an orphan girl being held prisoner in the Devil 's Bayou by treasure huntress Madame Medusa ( Geraldine Page ) .
Two of these mice , Bernard ( Bob Newhart ) and Miss Bianca ( Eva Gabor ) , set out to rescue Penny ( Michelle Stacy ) , an orphan girl who is being held prisoner in Devil 's Bayou by treasure huntress Madame Medusa ( Geraldine Page ) .