16 August 1952
In 1994, Isa joined the cast of the German soap opera Verbotene Liebe (Forbidden Love). She played the role of Clarissa von Anstetten for almost three years before she was temporarily written out in a successful kidnapping storyline, which went on for almost six months. Isa returned to the show and stayed another two years. In late 1999, Jank started having disagreements about her character but returned as planned after an eight-week break on-screen in February 2000. At this time the trust between Jank and the producers of the show seemed already broken and she left the show permanently in the summer of 2001 in a high-profile exit storyline, where Clarissa got her final battle with archenemy Tanja von Anstetten, played by Miriam Lahnstein. After a plane crash the character was presumed dead but even with Lahnstein's return in 2004, the show refused to confirm to the death of Clarissa.
In October 2005, Isa Jank returned to television taking the role of the antagonist Annabelle Gravenberg in the ZDF telenovela Wege zum Glück. Annabelle showed many similarities to Clarissa and Jank was even asked more often about her old role on Verbotene Liebe. Jank stayed with the telenovela for three years until Annabelle died on-screen in November 2008, shortly before the show ended.
Because Wege zum Glück was produced by Grundy UFA, the same production company responsible for Verbotene Liebe, rumors circled around the web that Jank eventually would return to her old show as Clarissa. The show itself showed lack of quality in storyline at this time and was in need of a character like Clarissa, but Isa Jank debarred the chance of a comeback. It is not known if meetings between the producers of Verbotene Liebe and Jank even took place. However more than two years later, in early 2011, Das Erste announced Isa Jank's return as Clarissa. She first reappeared in June 2011 and was part of a six-months special that was filmed on the Spanish island Mallorca, before joining her colleagues in Cologne. Jank stayed for another year and was then written off the show; with her last appearance on March 20, 2013. Verbotene Liebe was canceled in 2015 without another appearance from Jank.
In 2016, Isa Jank became a housemate in the fourth season of Promi Big Brother.