The series, which is based on the hit Norwegian show Pernille created by Henriette Steenstrup, is described as "a darkly comedic mystery about family – what it means to have one, to lose one, to pull one apart".
Collette stars as Lenni, a divorced social worker who “spends her days fighting for other people’s families while her own is in a constant state of hilarious chaos. The season follows Lenni through a new case, where the stakes couldn’t be higher as her work and personal life collides".
As well as Hereditary, the actress is also known to audiences for her roles in Little Miss Sunshine, Knives Out, The Staircase, Netflix's Wayward and Goodbye June.
She’s also set to take on the leading role in upcoming Audible Original, The Murder at the Vicarage, which is based on Agatha Christie's mystery novel of the same name.
Joining Collette in the cast are Ciarán Hinds (East of Eden), Dan Wyllie (Love My Way), Josh McKenzie (La Brea), Celeste Barber (The Letdown), Genevieve Hegney (Colin From Accounts), Arka Das (The Airport Chaplain) and Wayne Blair (Total Control).

Meanwhile, behind the camera, the show is being directed by Emmy and BAFTA Award winner Dearbhla Walsh (Bad Sisters, Margo's Got Money Troubles) and adapted by Sarah Scheller (The Letdown, Strife).
Bruna Papandrea, Steve Hutensky, Katie Amos, Avi Nir, Keren Shahar, Scheller, Walsh and Collette serve as executive producers, alongside Pernille creator Henriette Steenstrup, Bård Fjulsrud and Tanya Badendyck.
Production on Lenni is currently underway in Sydney, Australia.
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