Lord Voldemort: [as Harry, Ron and Hermione eavesdrop of him and Snape, suspiciously]The wand, does it truly answer to me? You're a clever man, Severus. Surely you must know. Where does its true loyalty lie?
Professor Severus Snape: With you... of course, my Lord.
Lord Voldemort: The Elder Wand cannot serve me properly because I am not its true master. The Elder Wand belongs to the wizard who killed its last owner. [pauses in realization]
Lord Voldemort: You killed Dumbledore, Severus. While you live, the Elder Wand cannot truly be mine. You've been a good and faithful servant Severus - but only I can live... forever.
Professor Severus Snape: My Lord... [Voldemort swishes his wand at Snape slitting his throat, Snape bleeds uncontrollably and falls on the window, Harry shudders in fear]
Lord Voldemort: Nagini, kill! [Nagini strikes at Snape several times, much to Harry's horror, Voldemort and Nagini leave and Disapparate]