After a tumultuous fall-out with NBC and more than nine months off television airwaves, Conan O’Brien returned to late-night last week, bringing his silly brand of humor back to hungry fans … on cable.

“Conan” debuted on TBS on Nov. 8 to 4.2 million viewers, taking the top slot in late-night for the evening. Though ratings dipped in his next three episodes — the show averaged 2.9 million viewers for the week — O’Brien easily topped his competition with younger viewers, which should please TBS executives and advertisers coveting the prized 18-49 demographic.

And that should be no surprise, as O’Brien’s shift from the older-skewed “Tonight Show” crowd to cable gives the manic redhead a chance to hearken back to the off-the-wall humor of his “Late Night” days, where O’Brien built his audience.

“Conan” doesn’t present anything radically new to O’Brien’s repertoire, though the show does feature a new theme song — likely because of the legal fallout from his NBC departure — along with titles for every episode and the disappearance of long-time band leader Max Weinberg. However, that’s not to say “Conan” doesn’t work, as it certainly does.

The show is highly reminiscent of “Late Night,” with hints of his stint on “The Tonight Show.” Sidekick Andy Richter returns to play off O’Brien, usually with the same sort of oddball humor that separates O’Brien from the likes of the drier Leno and Letterman.

Familiar staples have returned for “Conan,” including a fleeting appearance by the Masturbating Bear, O’Brien’s “string dance,” and gags, including a whale “breaching” the water from the oceanic view behind the desk, dousing guest Tom Hanks with water.

O’Brien took jabs in the premiere at his termination from NBC and his decision to move to cable.

“Welcome to my second-annual first show,” O’Brien said.

The decision to name the show “Conan” — the first late-night show to be named strictly after its host — is not anything wonderfully creative but capitalizes on the host’s brand, which no doubt got a boost in the wake of O’Brien’s departure from NBC.

O’Brien, however, said there was a different reason to name the show “Conan.”

“I did it so I’d be harder to replace,” he said in the premiere’s monologue.

Guests for the first week included Seth Rogen, Hanks — who appeared on O’Brien’s last episode of “The Tonight Show” — and Michael Cera, with musical guests Jack White and Soundgarden, among others.

The first week didn’t run perfectly, however. Though “Conan” returns much of the same production crew that was behind O’Brien’s shows at NBC, it appeared as if the crew was still adjusting to its new presence on cable.

In Thursday’s episode, for example, Richter, wearing a green shirt and tie, sat in front of a green screen with O’Brien for a parody on local news. The background image of a city skyline, presumably unintentionally, projected onto Richter’s clothing.

While the kinks are sure to be worked out, “Conan” is a welcome return for the fan-favorite late-night host. “Conan” presents a familiar style sure to please fans, and if the first week’s ratings are any sign, TBS will be content to let O’Brien continue to do so for quite a while.