Possible Clues:

• Allow fictional AI character to become mortal
• Having the potential to kill
• This might allow Henry to be the death of you
• "— Weapon" (Gibson/Glover film)
• Allowed spaceship's computer to become deadly
• ''--- Weapon'' (Mel Gibson film)
• Allow prince Henry to be very nasty indeed
• Obstruction by Henry proves fatal
• Toxic litre - alcohol, knocking number out
• ''--- Weapon''