Lena Mantler was born on June 17, 2002 in Stuttgart, Germany, and adopted together with her twin sister Lisa at the age of six months. In June 2015, the sisters began sharing self-created lip-sync videos on the online platform Musical.ly (since 2018: TikTok) - with growing success and tens of thousands of followers. On their Instagram account, created at the beginning of 2016, they reached almost two million followers within four months. The success is also explained by the fact that the two used mainly English songs for their Lipsync videos, which made them interesting for users outside of Germany.    

In the summer of 2017, the Mantler twins released their own song "Not My Fault" on YouTube, where it received 25 million views. They were named Influencer of the Year at the 2017 New Faces Awards. While their follower numbers continued to grow rapidly on Instagram, where they share their daily lives with fans through photos, videos, and produced Stories, the couple announced in March 2019 that they would be leaving TikTok due to security concerns; they returned to the platform about a year later, in May 2020.    

Lena and Lisa Mantler, who say they always dreamed of acting and took classes for it, made their debut as film actresses with supporting roles in the TV drama "Was wir wussten - Risiko Pille" (2019), as influencers promoting a new birth control pill for a pharmaceutical company as a lifestyle product. In June 2023, Lisa and Lena Mantler starred in their first feature film directed by Lea Becker: in the coming-of-age story "Get Up", they played dissimilar sisters who form a skateboarding clique with two friends. At the time, they had 13.5 million TikTok followers and nearly 20 million Instagram followers, making them the second most-followed German Instagram account after FC Bayern.