If anyone is able to get to London in August you might find one of these walking tours interesting. I have only toured with London Walks but was introduced to Bowl of Chalk by Mark Law (ThatDamGuide) who praises his tours. I plan on trying one of his tours the next time we are in London.
Thanks for the tip, it is now bookmarked for when we can re-plan our cancelled trip. Not at the point of doing too much planning and research as things will change when all reopens.
Johnnie is fabulous! Bowl of Chalk walking tours, bravo!
Our Naked Prague tour guide recommended Bowl of Chalk!