9x09: 19 Down (Full Episode) (From SuperNova) 

Superb. I just finished to watch it for two times one after the other. A perfectly polished high tension narrative, packed from beginning to end with great emotional content and charachter notations: from the videoconference with the serial killer (a really impressive interretation), to all the team reacting to Grissom's announcement that he's leaving.
A pearl: David's intense emotion totally surprises Grissom, once more unable to quite understand other people's affections.