British actress Bel Powley has joined Matthew McConaughey in drug dealer drama “White Boy Rick” to portray his addict daughter.

Set in 1980s Detroit at the height of the crack epidemic, “White Boy Rick” recaps the true-life story of Richard Wershe Jr. who became an undercover informant at the age of 14 before becoming a major dealer until he was arrested at age 17. The title role has not yet been cast.

Bruce Dern will play a grandfather while Jennifer Jason Leigh and Rory Cochrane are set to star as FBI agents who began working with Wershe Jr. as a confidential informant.

Yann Demange is directing the project for Sony-based Studio 8 as its second project following “Solutrean.” John Lesher is producing, as is Julie Yorn (who received a best picture Academy Award nomination for “Hell or High Water”) of LBI Entertainment. Protozoa Pictures’ Darren Aronofsky and Scott Franklin are also producing.

Powley, who is now 24, broke out with 2015’s  “The Diary of a Teenage Girl,” winning a Gotham Award for best actress and being nominated for a Spirit Award. Since then, she’s starred in “Carrie Pilby,” “A Storm in Our Stars” and “Ashes in the Snow.”

Powley is repped by UTA, Authentic and UK’s Curtis Brown.