"They" are the Nevills. They came over with the Conqueror and were big in English politics for hundreds of years, The family motto is "Ne Vile Velis" which roughly translates as "Don't Be Evil".
The church is full of their monuments. This one particularly caught my eye- both as a striking piece of sculpture and because of the story it hints at.
"What," I asked my informant, "Was a scion of the Nevill family doing in Colorado?"
I was hoping for a story of wild west gunplay. The actuality is that he was suffering from TB, went to Denver because his doctors told him the dry desert air would be good for his lungs- and died there from typhus.
He was lavishly mourned. Not only does he get a marble tablet, he also gets a window- in which he dresses up as St George, with his beefy face (clearly copied from a photograph) emerging from a fantasy suit of armour. St Michael- in the matching light- regards him with puzzlement- as well he might.
Had I wished and if I'd had a jemmy I could have levered up the metal plates in front of the high altar and gone down and admired his coffin. They're all there, the Nevills- the recent ones, anyway, stacked on shelves around the walls of their crypt. "It's very nice" said the woman, "Not spooky at all, very clean, very spacious. I could happily live down there..."