The comedy duo everyone wanted to see together has finally teamed up onscreen, Barbra Streisand and Seth Rogen... said no one, ever. The Guilt Trip isn't the worst comedy of the holiday season -- it's just a road trip without much road (and a comedy without much comedy). They appear to have spent about $37.00 on location shoots, and the rest of their time on a car rig. Their chemistry isn't just off, and ill-conceived, the two seem to be acting in two entirely different movies (odd, since they co-produced, and maybe should've worked this out before a table read). He seems to think he's in one of his usual Judd Apatow movies, and she seems to think she's reprising one of her mama Focker roles. She leaves him messages offering to pick up "slacks" for him at the Gap, and inviting him to join her Pilates class. The humor is gentle borscht belt, as she says of her senior singles mixer, "belle of the ball? more like bell of the bald." (Haw. Get it?) While Streisand fans will find little to object to in Rogen, it seems demographically unlikely that Rogen fans accustomed to the usual Apatow raunch will remain seated for this gentle noodge. Remember The Proposal? No? Exactly. Director Ann Fletcher's movies are pleasant enough, but err on the forgettable side. Streisand plays Jewish Mommy and empty nester Joyce Brewster. Seth Rogan is prodigal son returning from the west coast for a cross-country road trip pitching his eco-friendly organic chemistry wares (sort of like an oxy-clean, but drinkable). It is inconceivable that this schlub could get a pitch with KMart and Costco, but it would be a short trip (and a short movie) if he didn't. On a whim, after Mommy and Son have a little heart-to-heart about the boyfriend who got away (the one who preceded his late father), Andy invites Mom along on the road trip in hopes of reuniting her with her lost love out in San Francisco (unbeknownst to her). He does a little googling and "Andy" works for the same company Joyce knew him at. A secretary reveals he isn't married, just out of the country, and the plan is in place. (Apparently, this is a "period piece," as there's no facebooking or tweeting to see if the guy is "in a relationship," or perhaps "a civil union..." in San Francisco?) She seems a little lonely -- her defense against moving on to a new love is that she likes eating her M&Ms in bed, and never wants to hide them again. As shorthand character-revealing quirks go, it's a pretty lazy one. (Just find a man who likes M & Ms?) And thus, they hit the road in a compact car for eight excruciatingly long days that almost seem to play out in real time. They awkwardly listen to Middlesex on Books-on-Tape; they implausibly end up at a topless bar (where she does get a good line, "this place smells like strawberry gum."); she refills their water bottles at office water coolers where he's making pitches. They eventually have a little blowup, but it doesn't feel so much dramatic as it does contrived. "You think I'm stoopid?" she asks. "Well, you don't have to like me, but you do have to respect me. Now drink your fucking water." So, the air is cleared by the time they arrive in Texas, where Babs promptly enters a steak eating contest -- finish the meal in under an hour, and it's free. (Miss a bite, and it's a $100 bucks.) The only flaw, as Rogen points out, the steak is so massive, "that's like eating a poodle." As she gamely gnaws her way through the side of beef, she develops (what any competitive eater will recognize as) The Meat Sweats, and picks up an extravagantly handsome cowboy, Ben (the always-underrated Brett Cullen) as a Meat Coach. Although he's the goyest of the goy, and several rungs above a Jersey widow's league, the two click, and even sparkle a little. But Vegas must be endured, and then San Francisco, where, suffice to say, the original Andy doesn't materialize in the expected form. Still, the two have bonded. Mom may be striking out on a more independent future where she doesn't call baby boy 37 times a day, and the Son finally has optimistic business prospects. Eh, would it kill you to take your mother to a pleasant little move like this one, without all the profanity and nudity and explosions? No. No it would not. But, if you're looking for a truly inspired mother-son comedy to enjoy over the holiday weekend, find 1996's Mother on DVD (and streaming), starring Albert Brooks and Debbie Reynolds. He's hungry; she feeds him. He's not hungry; she feeds him. The sherbet in her freezer tastes like "an old foot," and she's named the "layer of protective ice," that has ruined it. Every tic is a master class -- and it's one Streisand and Rogen should've taken.