Isabel Prahl was born in Münster in 1978. Studying graphic design in Hamburg and literature, culture and media studies in Siegen, she eventually gathered professional film experiences through an internship at a production company in Cologne. In 2007, she enrolled as a post-grad student at the Kunsthochschule für Medien in Cologne. Her 2009 social spot "Armut kennt viele Geschichten“ won at the Young Director Award Festival in Cannes, received the award of the DEFA-Stiftung at the Schlingel Festival in Chemnitz, and also won one of the major awards at children's film festival Goldener Spatz in Gera/Erfurt. Her 30-minute graduation project "Ausreichend" (2011) also took home multiple awards, including the First Steps Award and the award for Best Foreign Short at Philadelphia Independent Film Festival. In 2012, Prahl received a fellowship award of the state North Rhine-Westphalia.

Following her graduation, Isabel Prahl directed numerous commercials, including spots for the insurance company Allianz and the Deutsche Knochenmarkspenderdatei (DKMS). Her feature-length debut, the family drama "1000 Arten Regen zu beschreiben" ("Different Kinds of Rain") starring Bibiana Beglau and Bjarne Mädel, premiered at the 2017 Black Nights Film Festival in Talinn, Estonia. The film also screened at the 2018 Max Ophüls Preis festival before being released in March that year. As co-producer, she was then involved in Barbara Ott's debut feature-length film and family drama "Kids Run," which was shot in 2018 and celebrated its world premiere at the 2020 Berlinale in the Perspektive Deutsches Kino section.   

She then directed the investigative TV film "Was wir wussten - Risiko Pille", first broadcast in October 2019 on ARD and focusing on the serious side effects of the birth control pill. At the time of the broadcast of this film, she was already shooting her next project, the TV crime thriller "Gefangen" from the "Tatort" series, which was shown on ARD in 2020. She also directed one episode each for the crime series "Friesland" (first broadcast in December 2019) and "Marie Brand" (first broadcast in June 2021) with Mariele Millowitsch as the commissioner.