Possible Clues:

• Tony winner Swoosie
• 'Heart of Darkness' character who cries 'The horror! The horror!'
• The protagonist of Heart of Darkness?
• ''Heart of Darkness'' trader
• Brando, in "Apocalypse Now"
• Brando, in 'Apocalypse Now'
• Literary character whose last words are 'The horror! The horror!'