EXCLUSIVE: Lauren Ambrose (Six Feet Under) and Nell Tiger Free (Game of Thrones) have been cast as two of the three leads in Apple’s upcoming psychological thriller series from M. Night Shyamalan and British TV writer Tony Basgallop.

While the plot of the series has not been revealed, I hear it follows parents Dorothy and Sean Turner, who have hired young nanny Leanne to help care for their newborn child.

Ambrose will play the mother, Dorothy Turner. Free will portray the nanny, Leanne Grayson.

The untitled project, which received a straight-to-series order, was created by Basgallop, who will write and executive produce the series. Shyamalan is executive producing and will direct the first episode.

The series will be produced by Shyamalan’s Blinding Edge Pictures, with the company’s Ashwin Rajan serving as executive producer alongside the Escape Artists team of Jason Blumenthal, Todd Black and Steve Tisch. Taylor Latham will co-executive produce.

Tony- and two-time Emmy-nominated Ambrose starred as Claire Fisher for five seasons on HBO’s Six Feet Under. She’s currently starring as Eliza Doolittle in Lincoln Center Theater’s production of My Fair Lady at the Vivian Beaumont Theater for director Bartlett Sher. Ambrose is repped by UTA, Kipperman Management and Sloane Offer.

Free played Myrcella Baratheon in Season 6 of Game of Thrones. She’s currently shooting the role of Janey in Amazon’s Too Old to Die Young. She’s repped by WME and Independent Talent Group in the UK.