"The night-blooming lousewort is just one example of the indigenous flora we will be examining on our evening walk!"―Edwina Cheltingham[src]
Edwina Cheltingham was an older plump British woman who taught about and protected the plants of the area around Glastonbury, England. She was one of the few in the area that knew the location of the real Holy Thorn, and considered herself one of its sacred protectors. She abhorred the Nazis. She was referred to as "Miss C" by Indiana Jones and Brendan O'Neal.
One day, in March 1945, she approached three men attempting to pick the thorn tree on Wearyall Hill and admonished them to stop. After she introduced herself, Professor Jones introduced himself, his son, and Brendan O'Neal and discussed with her the need to prevent the Nazis from making a spear shaft from the Holy Thorn as they attempted to re-assemble the Spear of Longinus. She immediately offered her assistance to help fight the Fascists.
At evening, she led a group of schoolgirls, including Sally and Molly, on a botanical walk of Glastonbury. On school grounds, near the Chalice Well, she brought her group into a tense situation: Dieterhoffmann and his Nazi comrades had captured the Joneses and O'Neal, and were planning on killing them. By bringing in a group of potential witnesses, Cheltingham's presence caused the situation to defuse. She whispered a rendezvous location to Indiana Jones, and attempted to shoo the plain-clothed Nazis away from the site, claiming that they needed permission. Jones used the diversion to escape. As she continued to lecture her girls, Jones rushed to grab the spear, causing Dieterhoffmann to accidentally shoot the spear tip, causing it to break in half. O'Neal and the Joneses then escaped. With the senior botanist and her class of girls around, the Nazis were restrained to not fire their guns after the fleeing trio.
Later that night, Miss Cheltingham met up with the three adventurers outside the Lady Chapel at Glastonbury Abbey after they encountered the mysterious Lady of the Chapel. She showed them the true thorn tree, and had procured for them a car and driver - one of her students, Rebecca Stein. After a grateful O'Neal gave Miss Cheltingham a kiss of thanks, she gave O'Neal a sprig of the true thorn for luck.