We've noted a lack of watchable medical drama in current network programming, but we're suckers for crossovers. The Grey's Privates event, as we call it while giggling, tops today's picks.

WATCH

Grey's Anatomy & Private Practice [9 & 10 PM ABC] - When we heard that Kate Walsh was spinning off down the coast, we assumed that Shonda Rhimes & Co. would be doing these crossovers twice a season. Sadly, that has not transpired and both shows have lacked the oomph of those early Grey's seasons. The crossover event begins tonight, though we must caution you, there is not all that much crossing over - most of that will take place next week. But the seeds are sown for all sorts of dramatic act endings:

Derek (Patrick Dempsey) has finally bought the engagement ring for Meredith (Ellen Pompeo) and is looking for the perfect way to propose. He even spills this secret to a patient (Jennifer Westfeldt - dueling against life partner Jon Hamm on 30 Rock). Meanwhile, Lexie (Chyler Leigh) wants to announce her relationship with Mark (Eric Dane). Meanwhile, in Santa Monica, Addison calls Derek after her brother Archer (Grant Show) suffers a severe seizure. Violet (Amy Brenneman) tells Sheldon (Brian Benben) and Pete (Timothy Daly) that she is pregnant.

If all the cast members of Grey's and Private aren't in one giant free-for-all orgy by the end of next week, we're officially done with these shows.

TiVo

30 Rock [9:30 PM, NBC] - Mad Men's Jon Hamm guest-stars as Liz's sexy new neighbor while Jack (Alec Baldwin) tries to impress Elisa's (Salma Hayek) grandmother who dislikes him because of his likeness to a Spanish soap villain. Meanwhile, Tracy (Tracy Morgan) tries to keep up with the hard-partying interns. This is top-to-bottom, A- through C-plot, the funniest show with jokes on television (Flight of the Conchords is up there, too, but that's all about mood, not jokes). Why the superlative? The sheer amount of casually racist and over-the-top offensive jokes they get away with is staggering — and permissible because every character is so clearly drawn. No one is trying to be scandalous to be scandalous (ahem, Gary Unmarried, etc.).

Hell's Kitchen [9 PM, Fox] - The boys and girls in Fox's promo cutting room really went all out for this week's episode of the poor man's Top Chef. We've been promised that the chefs will "put their bodies on the line" and "deal with consequences" and "break the rules" and Chef Ramsay will be pushed to the breaking point. Hmm, sounds like every HK episode, though this one is supposed to be extra crazy. No matter, we'll still be watching all the bleeps multiple times to guess which profanities were uttered.

KILL

Cat People [7 PM, Animal Planet] - Three cat-show competitors and their human handlers are followed as they strive for perfect scores. Competitive strategies are revealed and heartbreak is inevitable in the ultra-tense world of cat shows. This seems like a show we'd be into, but they go a bit too far in highlighting the weirdness. Anyone making non-fiction programming should watch The King of Kong and realize that there is a thick line between weird people and normal people, but they need to be treated equally by the director.