Emma Watson reveals 'most emotional moment' from 'Harry Potter' reunion

Among them were Emma Watson admitting to crushing hard on Tom Felton, Daniel Radcliffe writing a love letter to Helena Bonham Carter, and Watson nearly quitting the franchise.

There was one particularly sweet moment between Watson and Rupert Grint toward the end of the special where they discussed the inevitable time when they as well as Radcliffe had to figure out life after "Harry Potter" after eight films and 10 years together. Grint and Watson each got teary-eyed — Watson calling Grint "a pillar of my life," Grint asserting that "even though we don't see each other all the time ... we will always be a part of each other's lives."

"That was the most emotional moment for me," Watson recently told British Vogue. "When Rupert says things, he really means them. I was taken aback by how vulnerable and kind he was deciding to be so publicly. Similarly for Dan, it really touched me how reflective he had been over the years about how different it had been for me as a girl."

The 31-year-old actress and activist also addressed the hoards of fans begging for her to date Felton, despite the fact she is dating Leo Robinton and she and Felton never actually had anything romantic going on: "We speak most weeks, and we just think [the reaction] is sweet."

"Return to Hogwarts" is meant to commemorate the anniversary of the U.S. release of "Harry Potter and the Sorcerer's Stone" — the first of eight installments in the iconic, record-breaking film franchise.