John Birch, who wrote a fierce attack on vaccination, was a surgeon in St Thomas' Hospital London, so we filmed the module in the Old Operating Theatre, which once annexed the wards of St Thomas', and is now open to the public.

It's accessed through a twisting staircase in the gateway to St Thomas' Church, and it's a real gem: an early 19th century operating theatre, with raised viewing stands encircling the table where the bloody and brutal procedures (without anaesthetic!) would have taken place.