Gleecreator Cory Monteith tribute episode.
Speaking to reporters at a press call for American Horror Story, his other big TV project, the TV exec said the episode had been painful for the cast and crew.
"The episode is called The Quarterback, and Cory really was that to that group of people - and to me particularly," The Hollywood Reporter quoted him as saying.
"That group of kids particularly went through the limelight and became world famous at a very difficult age, and many of them really struggled with it.
"Cory obviously very much struggled with it, but never on the surface, and I think that's why everybody loved him.
"He was the most kind, the most generous - never a bad word for anybody."
Murphy also revealed that emotions had been running high during filming.
"I've never seen a crew that you can't continue shooting because they've left the room sobbing. It was very hard.
"I struggled even working on it because what you're seeing is what they felt not just about Finn but Cory. It's amazing performances across the board and everybody went into it with a lot of love.
"What I loved about it is when you write something like that, there's no right way to do it."

Cory's cause of death [uuid=5f46727d-fc93-4fd9-a3fe-5ff48ab0b370]was confirmed this week[/uuid].
The song list for the tribute episode has now been revealed, and is...
- Seasons Of Love (Rent)
- I'll Stand By You (The Pretenders)
- Fire and Rain (James Taylor)
- If I Die Young (The Band Perry)
- No Surrender (Bruce Springsteen)
- Make You Feel My Love (Bob Dylan, covered by Adele)