The Heart of the Matter - S4-E4
Character mistake: Ms. Bitzer says she's booked a trip to Iceland to experience the sun never setting. While the sun does set quite late there, Iceland is located south of the polar circle and does not have midnight sun. And either way, season four has been established as taking place after summer, so there wouldn't be midnight sun anywhere.
Continuity mistake: When Derek and Richard are in the lift talking, you can see Richard's head bandages under his hat. But when he removes his hat, his head is bare. (00:03:20)
Dr. Meredith Grey: At some point, you have to make a decision. Boundaries don't keep other people out. They fence you in. Life is messy. That's how we're made. So, you can waste your lives drawing lines. Or you can live your life crossing them. But there are some lines that are way too dangerous to cross.
Winning a Battle, Losing the War - S1-E3
Trivia: Several times in this episode, jokes are made about the residents thinking George is gay. Isaiah Washington was later fired for making homophobic remarks about T.R. Knight.