If you didn't stick with Christopher Guest's first foray into pay cable TV past its admittedly disappointing pilot, fire up your HBO Go and catch up in preparation for the first-season finale.

As we made clear in our original review, Family Tree got off to a slow start, but improved immeasurably with the second and third episodes. And by the time family treasure hunter Tom Chadwick (the terrific Chris O'Dowd) decamped from England to California to meet his American relatives, the series had become one of the funniest currently on the air. The finale finds Tom still in sunny Cali, where he meets a new cousin (another Guest regular Bob Balaban) and learns yet another family secret that should complicate his journey into the past even more come Season 2. HBO hasn't officially picked up a sophomore year yet, but it's gotta happen, right? They gave a second season to Enlightened, after all.

The Season 1 finale of Family Tree airs on HBO tonight at 10 PM, opposite a special Breaking Amish reunion show on TLC. At 8 PM check out Blue Man Group on Food Network's Cupcake Wars and a clip show of Tia & Tamera in advance of its Season 3 premiere on Style next Sunday.