By Michael Slezak
November 20, 2006 at 09:47 PM EST

In case you hadn’t noticed, PopWatch is a wee bit obsessed with Brothers & Sisters. But how can we ignore last night’s episode, with the introduction of Rob Lowe’s Senator Squarejaw? The answer is, we cannot, will not ignore it.

So where do we start? Do we start with A) the somewhat implausible plotline that Squarejaw, a dude with presidential aspirations and a messy recent divorce, would romantically pursue talk-show host Kitty (Calista Flockhart) after her on-air admission that she tried to persuade him to help her soldier brother avoid redeployment to Iraq in exchange for failing to ask him during a taped interview if he’d slept with his child’s nanny? (Whew!) Or do we B) cut to the heart of the matter and discuss whether Lowe and Flockhart exhibited palpable chemistry? I say “A,” because on Brothers & Sisters, it’s not really about plausibility. (Otherwise, we’d believe the world’s best forensic accountant wouldn’t have tried the first initials of all of Tom Skerrit’s kids — legit or not — as his secret account password.)

So, anyway, chemistry…yes, it’s there! Lowe even made it sound sexy (sort of) when Squarejaw offered Kitty a position…as his nanny. (!) The only negative for me is that, with Squarejaw around, Kitty’s on-again off-again flirtation with Josh Hopkins’ Warren is probably getting back-burnered. Then again, keeping in mind that even Kitty’s mother thinks her daughter “conducts her personal life like a contestant on a French game show,” perhaps our gal will find room in her heart — or at least her boudoir — for both.

addCredit(“Brothers & Sisters: Ron Tom/ABC”)

In non-Lowe related matters, the roadtrip? Awesome. EspeciallyBrenda/Sarah (Rachel Griffiths) going on a bender at that military barand ending up feeling “like Nick Nolte’s mug shot” the next morning,and Kevin’s totally predictable but nonetheless adorable dalliance withHot Soldier Guy. My burning question of the week, though: Who shouldthe producers get to play unseen half-sister Rebecca? I’m throwing myinconsequential vote to Tina Holmes (Six Feet Under‘s ferret-faced Quaker Maggie), if only because she and Griffiths do that tension thing so well. How ’bout you, PopWatchers?