Possible Clues:

• Coup de grace
• Poor old hat web gets the coup de grace
• Fatal strike
• Russell Crowe delivery to Joaquin Phoenix, in “Gladiator”
• Black inside, rotten old wheat in lethal buffet
• Doctor hated smack — it's a killer
• No coming back from that stab in the back
• Fatal hit
• Who tabled amendment for coup de grâce?
• Sudden life-destroying event