Already during her training as a state-approved musical actress at the European Musical Academy Bremen, Mareike was on stage in numerous productions and roles, such as "Amely Crachit" in SCROOGE AND THE GHOSTS OF CHRISTMAS, as a soloist in the Rock Show THE SHOW MUST GO ON - QUEEN IN CONCERT and the cult musicals LINE 1 and NON(N)SENS. She also sang at the international music festival CELEBRATE DURBAN in South Africa. After her training, she received an engagement as the witch Ursula in THE LITTLE MERMAID at the touring theater Theater Liberi. In 2015/16 she appeared in the Staatstheater Mainz in the musical SPAMALOT and at the same time toured as a singer and presenter with the CIRCUS FANTASIA. In 2017 and 2018 she traveled around the world as a soloist with the MS Amadea. In 2019 she once again returned to the Theater Liberi and played Pinocchio's conscience, the cricket.