With her mental state weakening, Angel fears for Darla's safety at Wolfram and Hart. We the viewers also get more insight to how Darla and Angel's lives used to be, via flashbacks.
Previously I have not cared that much for Darla. This episode may be a turning point for me. I was really interested in what was going to happen to her and if she would be ok. Then when she left ran out of the hotel at the end, I was sad and I wanted her to come back. So now I like the character of Darla.
I've always enjoyed flashbacks of Angel's life before he got his soul, so naturally I enjoyed this episode. It was always interesting to me to compare Angel to Angelus.
There was a lack of Cordy and Wesley bickering in this episode, which was disappointing, but the flashbacks made up for that.