Kristen Wiig, Alexander Skarsgard and Bel Powley have joined the cast of the pic from first-time writer-director Marielle Heller.

Caviar and Cold Iron Pictures have come aboard to finance and produce The Diary of a Teenage Girl, based on Phoebe Gloeckner’s graphic novel. The 1970s-set film, which is filming in San Francisco, follows a brutally honest teenage artist (Powley, in her U.S. feature debut) as she attempts to navigate her way through an affair with her mother’s boyfriend. Bert Hamelinck and Madeline Samit of Caviar (Nymphomaniac) will produce along with Miranda Bailey of Cold Iron and Anne Carey of Archer Gray. Amanda Marshall and Michael Sagol are executive producers along with Jorma Taccone.

Wiig, a 2011 Oscar nominee for her Bridesmaids screenplay, is onscreen in Anchorman 2: The Legend Continues and The Secret Life of Walter Mitty. Skarsgard stars on HBO’s vampire drama True Blood, which is ending its run after next season, and appeared in the recent features The East and What Maisie Knew. Heller is an alum of the Sundance Institute Directors and Screenwriters Labs. UTA will handle domestic sales of the film. K5 International will handle foreign sales.