Martha Plimpton is ready to stream.

The actress has signed on to star in HBO Max's Generation, the pilot executive produced by Lena Dunham.

Picked up to pilot Aug. 19, Generation is a dark yet playful half-hour dramedy that follows a group of high school students whose exploration of modern sexuality tests deeply entrenched beliefs about life, love and the nature of family in their conservative community.

Plimpton will make her streaming series debut and star as Megan, a magnetic Adderall-fueled type-A Orange County mother whose core convictions clash with the values of her children's generation. The actress will play the mother of the two leading roles that have yet to be cast.

Generation was created by Daniel Barnz (Cake, Phoebe in Wonderland), who also will serve as writer and director. His 17-year-old daughter, Zelda Barnz, is set to co-write the script and co-executive produce the pilot. Daniel's husband (and Zelda's father) Ben Barnz will also exec produce via the couple's We're Not Brothers Productions banner. Dunham (Girls) will exec produce via her recently launched Good Thing Going Productions banner.

Plimpton's credits include series-regular roles on The Real O'Neals and Raising Hope, as well as the features The Goonies, The Mosquito Coast, Running on Empty and 200 Cigarettes. She is repped by Innovative and Markham Froggatt.

Generation is part of HBO Max's first pilot slate. WarnerMedia-backed HBO Max will launch in the fall in beta, with scripted originals set to roll out in 2020. Cable crown jewel HBO will be central to the upcoming service, with its library titles — including Game of Thrones and The Sopranos — joining others including Friends, The Big Bang Theory and likely Seinfeld. HBO Max has been on a spending spree as it ramps up originals to stock the platform as it looks to compete with both established streamers (Netflix, Amazon, Hulu) and new arrivals (Disney+, Apple, NBCUniversal) in the space. HBO Max's scripted roster includes a female-focused take on Dune, the Kaley Cuoco vehicle The Flight Attendant, a new take on Gossip Girl and Tokyo Vice, starring Ansel Elgort, among other comedies and dramas.