Lisa and Selma are chatting about green energy at Das Marek when Yara shows up and tells them about the flea market she's organizing. This is the first time Yara has met Selma, though she knows that Nico has a big crush on her.

Lisa wants her class to try giving up plastic for a week. She quickly realizes that it's more challenging than she first thought, but luckily, some sweet treats come in cardboard packaging too.

The environment concerns everyone—including these roommates! How can people be convinced to recycle and sustainably change their behavior as consumers? The four discuss what could be done.

Yara and her landlord are talking about climate change. Yara is appalled by how some people are so indifferent to the issue.