Possible Clues:

• Wretched involuntary action
• Flickering ... or, read differently, what connects 16-, 20-, 36-, 38- and 50-Across?
• Family in flashy clothing, damned
• Almost unable to see, man on board may be this
• Wretched crooner gets to join in
• Damned response to grit in eye?
• Quick closing and opening of the eyelid