Derek decides to quit after learning that more of his patients have died than survived; Izzie's interns make an unsettling discovery about "Patient X."
| Title | I Will Follow You Into the Dark |
|---|---|
| Genres | Drama |
| Release Date | 2009-03-12 |
| Episode Runtime | 00 Hours 50 Minutes |
| Season Number | 5 |
| Episode Number | 17 |
| Production Companies | The Mark Gordon Company, shondaland, ABC Studios, Touchstone Television, Entertainment One Television, Lionsgate Television, ABC Signature, Trip the Light Productions |
