Jason Isaacs has joined the cast of 'Sex Education' season 3, and he's not the only one.

The hit Netflix series resumed production in Wales last August. There will be some new faces joining the gang at Moordale High.

Jason Isaacs will play Peter Groff, the headmaster's "more successful and not very modest older brother", and uncle to Adam (Connor Swindells).

You'll recall how the season 2 finale saw Michael Groff (Alistair Petrie) fired and separated from his wife Maureen (Samantha Spiro). Now he's staying with his brother.

Another new cast member is Jemima Kirke, who you may know from the series 'Girls'.

She will play former Moordale student and new headmistress Hope.

Her goal is "to turn Moordale back into the pillar of excellence it’s always been." Wonder what that will mean for sex education counselor Jean (Gillian Anderson)...

Recording artist-songwriter Dua Saleh is another addition, joining in her acting debut.

She'll portray Cal, a nonbinary student at Moordale, who instantly clashes with Hope’s new vision for the school.

Kirke and Isaacs are guest stars, while Saleh is recurring.

All the regulars like Asa Butterfield, Ncuti Gatwa, Emma Mackey, Aimee-Lou Wood and more will be back in season 3.

It's coming sometime in 2021.