EDITOR'S NOTE: Showtime is offering a free preview this weekend, Jan. 11-13, which allows non-Showtime subscribers to catch Sunday night's lineup this week. Check the Showtime website to see if your cable provider is participating.

HBO and Showtime butt heads, intentionally and aggressively, Sunday night, launching new seasons of their respective comedies directly opposite one another — starting with HBO’s Girls…

It’s quite a TV battlefield. At 9 p.m. ET, HBO begins with Season 2 of Girls, the highly acclaimed, sometimes controversial twentysomethings comedy by and starring Lena Dunham (left), and follows that at 9:30 p.m. ET with Season 2 of Enlightened, the Mike White-written comedy that stars Laura Dern as a corporate drone with a newly awakened social conscience. Those shows are repeated in the 10 p.m. ET block — but during both showings, they’re opposed by new episodes of returning series on Showtime.

Over there, the 9 p.m. ET hour is filled by Season 3 of Shameless, the Americanized version of a popular British series. Showtime’s version stars William H. Macy as a scheming, unreliable patriarch of a family of young con artists.

At 10 p.m. ET, Don Cheadle and company return with Season 2 of House of Lies, about a team of oily, quick-witted corporate consultants. And at 10:30 ET, David Duchovny returns with Season 6 of Californication, a comedy about hedonism on parade.

That’s a lot of fresh comedy — and an awful lot of intentionally abrasive characters. Every major character, in every one of these shows, has more flaws than a Transformers movie plot line. But they’re entertaining — Girls most of all, but all of them have their moments, and their standout performances.

All of these series are showcase vehicles for their leads, all of whom deliver strongly — especially the unflinchingly brave Dunham and Macy, who appear to relish the least attractive and comfortable aspects of their characters. The first few shows of the season feature a dinner party on Girls that is rivaled in squeamy discomfort only by an early family-reunion scene on Shameless. The silences are crushing — and the words between those silences even more so.

But it’s not just the leading roles that propel these programs. In addition, supporting performers deliver performances riveting enough to demand attention and warrant praise: Allison Williams as Marnie on Girls, Mike White as Tyler on Enlightened, Emmy Rossum (far right) as Fiona on Shameless, Kristen Bell as Jeanie on House of Lies, and both Evan Handler as Charlie and Pamela Adlon as his ex-wife Marcy on Californication.

Time slots aren’t as meaningful as they used to be, so all these shows, like water, eventually will find their own levels. But the confidence of upstart Showtime to counter-program directly opposite powerhouse HBO says a lot — as does the hardly coincidental shared trait of these shows, spotlighting a central character who’s not always, and sometimes not at all, likeable.

I’m reviewing all these series, focusing on Girls, Friday on NPR’s Fresh Air with Terry Gross, so tune in, or visit the Fresh Air website after 5 p.m. ET Friday, to catch it. Also check out Ed Bark's review of Girls in Uncle Barky's Bytes.

Then decide which of these Sunday shows is for you. But don’t forget: Sunday night at 9 p.m. ET also is the evening of PBS’s Downton Abbey and CBS’s The Good Wife — and, this week, Tina Fey and Amy Poehler co-hosting NBC’s live coverage of The Golden Globes Awards.

Thank the TV gods for DVRs…