Christopher Kane is a clothing store on Carpenter Street, Mayfair, London. It was used for the filming of the fictitious Vashti in episode 3 of The Cuckoo’s Calling.
Robin takes things into her own hands and extracts information about Lula Landry’s visit there from a staff member. This is where Cormoran sees Robin in the green dress. Strike also goes back here later on to get the audio file of Lula Landry talking from the shop assistant.
You can find Christopher Kane on Google Maps here.