The following excerpt is from prefixmag.com:
Actor/writer/director Christopher Guest is set to co-write (with Jim Piddock) and hopefully direct a new show entitled Family Tree.
Starring Bridesmaids’ Chris O’Dowd, the mockumentary series has been picked up by HBO and a deal with BBC is in talks. The series would follow Tom Chadwick (O’Dowd) as he uncovers his family’s history. There’s no word yet on when the show will premiere, but it’s expected to have “around eight episodes.”