The House of Black:
Lily James as Cassiopeia Black
Matthew Goode as Cygnus Black
Evas Green as Druella Black
Katie Mcgrath as Bellatrix Black/Lestrange
Keira Knightley as Andromeda Black/Tonks
Sarah Gadon as Narcissa Black/Malfoy
Timothée Chalamet as Regulus Black
The Marauders:
Aaron Taylor-Johnson as James Potter
Ben Barnes as Sirius Black
Andrew Garfield as Remus Lupin
Jamie Bell as Peter Pettigrew
Others:
Anya Taylor-Joy as Modesty Bobbin
Ben Schnetzer as Bertie Nott
Sophie Skelton as Lily Evans
Louis Garrel as Severus Snape
Harry Lloyd as Lucius Malfoy
Tom Hughes as Rabastan Lestrange