Face of Evil.
It starts with a very odd bit to camera with the doctor. I haven't watched this in a very long time.
Leela is a big change from Sarah Jane, I don't remember there being an outcry at her outfits back when this was first on but I guess there must have been.
I'm just watching the Louise Jameson Doctor Who story documentary. She says she insisted on the flap at the back. The original costume must have been very drafts.