Revealing mistake: When Alex is talking to Rebecca Pope at the end of the episode, we hear Alex say "Now I know more about you than my friends." Watch Rebecca's left eye on the right if the screen when she says, "That's pathetic." Someone did a bad job of editing the CGI and we see a phantom eye over her left eyebrow.
Grey's Anatomy (2005)
1 revealing mistake in season 3 - chronological order
Continuity mistake: When attaching the arms during surgery, they show the same arm with the tattoo "Nicole" pink up twice instead of showing both arms.
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.