When Matthew Perry's new NBC sitcom "Go On" debuted back during the Summer Olympics, I wasn't entirely sure what to make of it. On the one hand, it seemed a better vehicle for Perry than "Mr. Sunshine" (Yay) did, and the writing seemed to take the idea of a grief support group seriously. On the other, the pilot felt an awful lot like the first episode of "Community," a niche comedy representing a creative direction NBC was openly desperate to get away from, and the pilot, while tasteful in its comedy, also wasn't incredibly funny. Could this possibly work, or would this be yet another high-concept sitcom trying to forget its premise as quickly as possible?

Tonight's episode is the eighth, more than a third of the way through this first season, and a few things are more clear. First, "Go On" has been a modest success, thanks to a strong lead-in from "The Voice."(*) Second, the creative team haven't run away from the concept, as the show frequently deals with Perry's character grappling with the death of his wife (a few weeks ago, he began packing on the pounds through "grief eating," and the most recent episode had the group helping him through his first birthday as a widower) and to a lesser extent with the problems that brought all of his weird new friends to the group.

(*) Remember when NBC executives kept talking about how the Olympics were going to be the catalyst for the network's escape from the basement? Well, NBC is the number one network so far this season, but that has less to do with the Olympic halo effect — since "Animal Practice," the other show that got an Olympic sneak preview, is canceled, and "Go On" is a modest success at best — and more to do with having "The Voice" on in the fall, and having a show in "Revolution" that "Voice" viewers wanted to watch more than they did "Smash."

Third, despite Perry's obvious star power at the center, "Go On" has done right by its large ensemble cast, and particularly by Julie White and Brett Gelman as the most and least stable members of the group, respectively, and by John Cho as Perry's boss at the sports radio station. The series does feel like it's about a group, and not just the sarcastic guy from "Friends" who just joined it. Overall, it's become a sweet series that's embraced its tricky subject matter.

That said, laughs still come in fits and starts, most frequently from the withering scorn of White's Type-A attorney Anne or the loopy inappropriateness of Gelman as the mysterious Mr. K. Though Perry hasn't lost his flair for deadpan sarcasm, the best humor involving his character tends to be how the others react to him (tonight's episode makes it plain how low their expectations are for him) than in what he does.

At the same time, tonight's episode illustrates the overall appeal of the concept, and the ensemble. Perry's Ryan becomes addicted to "Halo" as a way to tune out the rest of the world — and thoughts of his late wife — and becomes closer to the group's youngest member, Owen (Tyler James Williams) as a result. But what Ryan expects to be a superficial, substance-free friendship becomes more complicated as he gets to know Owen, who joined the group after his older brother went into a coma following an accident. Perry and Williams have a strong rapport, and there's a nice subplot about what happens when a member of the group tries to "graduate," which is less about that issue — this is a sitcom with a stable cast that, in success, will not want to be getting rid of people, I suspect — than about the shaky qualifications and confidence of group leader Lauren (Laura Benanti), and the lengths the group will go to to support her.

Long-term, I'd like to see "Go On" more consistently mine laughs from what's proven to be a strong cast. It's still my third comedy choice in the timeslot (after FOX's "New Girl" and ABC's "Happy Endings"), but I've found it consistently more engaging than I expected back in the summer.

Alan Sepinwall may be reached at sepinwall@hitfix.com

Alan Sepinwall has been reviewing television since the mid-'90s, first for Tony Soprano's hometown paper, The Star-Ledger, and now for HitFix. His new book, "TV (The Book)" about the 100 greatest shows of all time, is available now. He can be reached at sepinwall@hitfix.com