UPDATED: Family Tree has added three more recurring guest stars: Matt Griesser as Greg, the American cousin of Chris O’Dowd’s character Tom; Maria Blasucci as Greg’s girlfriend; and Lisa Palfrey as the wife of Tom’s father, played by Michael McKean.

PREVIOUS, 8:26 AM: Nina Conti and Tom Bennett have joined as regulars the cast of Family Tree, HBO‘s single-camera documentary-style comedy from Christopher Guest that stars Bridesmaids‘ Chris O’Dowd. Amy Seimetz has also joined as a recurring on the project, which received a straight-to-series order in August. O’Dowd plays 30-year-old Tom Chadwick, who, having recently lost his job and girlfriend, has a rather unsure sense of his own identity. When he inherits a mysterious box of belongings from a great aunt that he never met, he starts investigating his family lineage and uncovers a whole world of unusual stories and characters and a growing sense of who he and his real family are. Conti, who appeared in Guest’s film For Your Consideration, will play Tom’s sister; Bennett will play his best friend. Seimetz will play Ally, an aspiring writer who works in a bookstore and who Tom meets in unusual circumstances when he visits Los Angeles. Eight episodes have been ordered for Family Tree, which will also air on BBC Two in the UK.

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