LONDON — When SOFIA ISELLA took the Wembley Stadium stage to open for Taylor Swift, she just kept thinking, “It’s just Thursday night. The most insane Thursday night.”

Isella (who capitalizes her name artistically) served as the first of five women to kick off the Eras Tour show at Wembley this month before opening act Paramore. On Thursday, the 19-year-old shot a surge of energy over the thousands of bedazzled fans trickling in. After her opening song "Hot Gum," she ripped off her white tee uncovering a cedar brown leotard.

“This is the most insane view I’ve ever seen in my entire life,” she said to Wembley before embarking on a 25-minute, six-song setlist that included "Sex Concept," an electrifying, provocative single released Saturday morning. Isella whisper-sings her poetry through haunting echoes in the new track. Her lyrics hold power over a man, as she plays hard-to-get in a lingering game of lust, "Cause I'm the backyard heathen / The girl he's dreaming / I'll bend him over backwards / Give him something to believe in."

To prepare for playing a sold-out and packed Wembley — a moment very few artists get — Isella says she engaged in daily cardio at Regents Park, a 410-acre grassy pocket of Northwest London.

"I ran around in circles everyday in a big open field while singing the set list," she says. "I got a lot of looks."

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The classically trained violinist picked up her instrument at the age of 3 and deployed her songwriting pen at the age of 8. Born in California, she lived in the Gold Coast of Australia for the past few years, quarantining for her dad's job amid the COVID-19 pandemic. Recently, Isella moved back to Los Angeles. Her biggest influences include Trent Reznor, Beck, Sylvia Plath, Margaret Atwood, Mona Awad, Anne Sexton and Taylor Swift.

She woke up to the news she was opening for Miss Americana at 7 a.m. on March 30 when her mom came barging into her room.

"My mom came screaming into my room from an email with the offer," she says. "I just kept repeating, 'Wow.'"

Swift wrote Isella a letter.

"What she wrote in there touched me so hard, all the black ink under my eyes was gone after reading," Isella says.

The Eras Tour star thanked Isella in her opening "Lover" speech on Thursday, asking the crowd to show appreciation. The bevy of 92,000 fans answered with a roar.

Backstage, Isella wasn't able to meet up with Paramore or surprise guest Ed Sheeran. "Ed was a surprise to me as it was everyone else," she says. But she did meet Swift.

"[Taylor] called to meet me right before she went on stage, and she was so, so kind," Isella says. "Everything you would hope she'd be. She didn't have to do all these kind things for me. She just did."

Up next, Isella is releasing her "I Can Be Your Mother" EP on Sept. 6. Immediately following the roll out, she will play a list of California shows in Santa Cruz, San Francisco, Santa Ana, Los Angeles and San Diego. Her Los Angeles show will be her first hometown concert at the Echo on Sept. 11.

"You can expect that I will smell all of you because you will be two inches from my face," she says. "I love miniature venues for that."

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