Grey's Anatomy

The character Alex Karev was not in the original pilot script; his role was inserted into the pilot as an afterthought in order to provide a foil, as well as male companionship for Dr. George O'Malley. Since he wasn't added until after the pilot was shot, scenes with him were either re-shoots or digitally altered.

Shonda Rhimes said on an interview that she had a clear idea thought for the show's end, but its success kept growing to the point of her ending no longer being proper, so she decided to use the idea on a storyline and come up with another ending.

Singer Taylor Swift is a big fan of the show. She even named one of her cats Meredith Grey, after the main character.