Longendyke, the middle child of three girls, was born and raised in the small town of Hurley, in the Hudson Valley of New York.

[2][3][4] While working as a waitress, Longendyke's test photos were chosen to be in a Saint Laurent campaign,[3] alongside British-French singer Charlotte Gainsbourg and American supermodel Amber Valletta.

[5] Her first runway show was for the former Calvin Klein Collection label, and she walked for Saint Laurent, Chanel, and Valentino among others.

[3] In the 2019-2020 season, she walked in 58 shows,[6] twice as many as her contemporaries, for brands including Vera Wang, Burberry, Ralph Lauren, Victoria Beckham, Prada, Givenchy, Louis Vuitton, Miu Miu, and Chloé.

[9] Longendyke has appeared in campaigns for Louis Vuitton, Chanel, Celine, Michael Kors, Michael Kors Gorgeous Fragrance, Mango,[2] Isabel Marant, Calvin Klein, Calvin Klein Euphoria Intense Fragrance, Prada, Chloé, Tod's, and Zara.