Possible Clues:

• He outwitted robbers and cut short excuse in court - a clever chap
• Legendary password user
• Hero from Arabian Nights who said ''open sesame''
• Speaker of 17-Across
• ''Open sesame'' sayer
• Pantomime character who took on 40 thieves
• - - and the Forty Thieves
• Pantomime character who speaks the opening words
• Legendary woodcutter
• Arabian Nights hero who opposed forty thieves