VIDEO: DOWNTON ABBEY Cast Previews Season 4!

Writer and creator Julian Fellowes, executive producer Gareth Neame and actors Michelle Dockery (Lady Mary) and Laura Carmichael (Lady Edith) discuss what's ahead for the inhabitants of Downton Abbey next season, premiering January 5th on PBS.

On the new season of the historical drama, Emmy, Golden Globe and SAG award-winner Paul Giamatti (John Adams, Sideways, Barney's Version, Cinderella Man) will join the cast portraying Cora's maverick, playboy brother Harold, starring alongside the iconic Shirley MacLaine and the regular cast members.

Managing Director Carnival Films and Executive Producer Gareth Neame says: "Downton Abbey has seen many great characters visit the house over the years and we couldn't be more thrilled to welcome the new faces that will be joining the regular cast of Downton Abbey in Season 4. We hope audiences will be as excited about them as we are."

Giamatti joins new cast members, including:

Tom Cullen as Lord Gillingham, an old family friend of the Crawleys who visits the family as a guest for a house party

Nigel Harman as Green, a valet

Dame Harriet Walter as Lady Shackleton, an old friend of the Dowager

Joanna David in a guest role as the Duchess of Yeovil

Julian Ovenden as aristocrat Charles Blake

Dame Kiri Te Kanawa as a guest who sings in the house

Gary Carr as a jazz singer named Jack Ross

Downton Abbey is a Carnival/Masterpiece Co-production. It is written and created by Julian Fellowes. Gareth Neame and Julian Fellowes are Executive Producers.