The Irish actor, who played Luna Lovegood, joined the franchise in the fifth entry, Harry Potter and the Order of the Phoenix, which was released in 2007.
Lynch, 29, has now revealed she was so nervous before arriving on set that she would “rehearse conversations” she was about to have with her child co-stars.
“Because I was such a big Harry Potter fan, I was very nervous around those three and intimidated by them,” she told Us Weekly.
“I used to be in the car on the way to set, kind of rehearsing conversations I’d have with them. And, obviously, the conversations never worked out like that.”
She said that Watson, who played Hermione Grainger, “was always so nice to me, and made an effort to get to know me and make me feel at home, which was a huge deal coming from her”.
Reflecting on her final day of filming scenes for Harry Potter and the Deathly Hallows: Part 2 (2011), Lynch said: “There was a sense of joy, euphoria, sort of tinge of sadness. Very much sort of sweet.”
She added: “I wasn’t ready for it to end, so I didn’t, I just kind of pretended it was another day on set. I definitely cried, but I didn’t cry until I went to say goodbye to the producers in the office. To me, that’s when it was like, ‘Oh, this journey is ending.’”
Draco Malfoy actor Tom Felton recently cleared up confusion surrounding fan speculation of a possible romance with Watson.
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While the pair have remained friends since the film series came to an end, fans have long speculated that they spent some of that time dating.
“We are something as far as we’ve been very close for a long time,” the actor told Entertainment Tonight.
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