Lady Blanders turns back toward us. “So, you see, I have an airtight alibi. And even if I didn’t, what could my motive be? Why would I possibly want to murder Tracy Penny, a common hairdresser? What is she to me? An utter insignificance.”
Allusion to The Mirror Crack'd - though likely not the same solution? Still - she could have spoken about anything during the appointment.
