Derek, Addison and others in “Who's Zoomin' Who?”

Derek

[he sees Addison] Meredith, I am so sorry. [Addison walks over] Addison. What are you doing here?

Addison

Well you'd know if you'd bothered to return any one of my phone calls. [she turns to Meredith] Hi. I'm Addison Shepherd.

Meredith

Shepherd?

Addison

And you must be the woman who's been screwing my husband.