Kegels? More like bagels, am I right ladies? Oh how we laughed.

If you’ve yet to fully appreciate just how divergent men and women truly are, then ‘I Don’t Know How She Does It’ makes a pretty retrograde case. Example: women keep lists and men don’t, since men are too busy sleeping to care about such things. Likewise, it’s abundantly clear that men are ill-equipped to handle ‘women’s issues’, which is why mammograms are such a fun excuse to use around the office. Ever notice how a man leaving to care for his sick child is deemed heroic, while a women who does the same lacks commitment? How is it that being ‘one of the boys’ is frowned upon, yet displays of femininity are likened to unhinged emotionalism? If only women could have it all. If only men could understand.

Sarah Jessica Parker is the wife and mother who dares. The wife who considers herself an equal. The mother who returns to work and still manages to beg, borrow or steal a cake for the children’s bake sale. Such wonder women are commonly argued to be the unsung heroes of our time, a cause to which I’d be more sympathetic if only Kate weren’t so vocal in insisting upon it. She even ropes in Allison (Christina Hendricks) to confirm as much in occasional pieces to camera. Curiously, many of the film’s gender banalities are of her doing, so much so that she seemingly had very little time to feature in the storyline itself. Perhaps she’s a metaphor for the woman who can’t have it all.

Husband and wife at work, children in tow. For a while that seems okay, and no one is happier than Richard (Greg Kinnear) when his wife lands a shot at a big city contract. Nothing will go wrong, Kate assures. She’s got this. Do we believe her anymore than she believes herself? We know something will happen, just as we know she’s destined to feel guilty about it. Guilty she couldn’t be there, guilty for being a woman. Guilty looks will abound, tumbling from every baby, child, infant and spouse the film can find.

Despite the accepted wisdom that men can’t possibly be expected to work with female colleagues without becoming to all that simmering sexual tension, high flying Jack (Pierce Brosnan) is surprisingly understanding of his co-star’s besieged womanhood. Indeed, for all its fascination with outdated gender stereotypes, Jack and Richard make a rare case for the sympathetic male lead. Even Kate’s eventual will-she-will-she-how-could-she plot is handled with insight bordering on maturity. How sad that such mistakes are not repeated elsewhere, either in the pantomime misogyny of her chief rival (Seth Meyers), or Momo: her disturbingly robotron assistant. Oliva Munn is seen to embody a monotone succubus, whose fertility represents something of a Chimera nightmare until she eventually finds a cause that melts that stony heart into infantile mush.

In this one-woman salute to mothers everywhere, Parker, Kinnear and Brosnan do fine work. None of them try very hard, but that’s the joy of talented actors: when they’re slumming it like this, they don’t really have to. The conclusion is as you’d expect: Kate learns to sacrifice, and Momo knows now why we cry. “It’s snowing!” Kate squeaks, and with a hop she’s gone. There’s a snowman to be built; in high heels, no less. No man is going to stop her this time. She’s worth it, see?

Love is a losing game, love is a numbers game, and sometimes it’s both. Ally Darling lives in a world easily mistaken for that of Carrie Bradshaw, in which magazine fluff pieces could still send a girl’s head into a spin. One article in particular reads like the death rattle of Ally’s last viable egg. It postulates that number of sexual partners has an inverse correlation with happiness; sleep with enough guys, the theory goes, and you ain’t never gone git married. The headline also happens to be “What’s your number?” so, you see, it’s not just a clever title.

Anna Farris is an actress who throws herself into work like no other I can name. She has been in so many bad movies – almost irredeemable movies – and yet somehow managed to convince us of her unshakeable belief in each and every one. That’s an admirable quality which serves her just as well when the material has a modicum of potential. What’s Your Number remains stubbornly derivative and oftentimes forgettable. It is not Lost in Translation, or even Just Friends. But as a genre exercise and easy Friday night rental, it succeeds more often than not.

The article puts the average number of sexual partners at 10.5, which kinda has to make you wonder about the half. Ally’s total is a slightly less chaste 19, and not an especially good 19 either. One was Gerry, the puppeteer, who kept the puppet on throughout. Then came Gay Tom, and Eddie who wanted to keep it casual. Disgusting Donald was just that, while Jack emigrated to Africa to head up the kind of worthy foundation you see on TV charity appeals. The list goes on, and Ally revisits them all in the hope one might have blossomed into the proverbial frog prince. A sweet fairytale, perhaps, except one of those Prince Charmings is now a gynaecologist, who recognises her only upon renewing acquaintance with her vagina.

That’s a word you’ll hear more than during the course of the film, owing to a script clearly liberated by last year’s R-Rated Bridesmaids. Of the two, this is the more traditional fare, which is to say it never stoops so low as to recreate that bridal shop scene. Not that it has an overly positive message of its own, but it can at least find comfort in not having utterly demeaned its intended audience along the way. Such an opinion is unlikely to find many supporters. If this had only come with Judd Apatow and an SNL alum attached, the reception might have been considerably warmer.

Even so, there’s no more than half a movie here. The first hour does its best to bury anything not frighteningly predictable. Ally rekindles relationships best left forgotten, and dissuades the rest with clumsily laid plans. On she goes, the little blonde hamster in her wheel of futility, until she finally comes to rest upon a handsome neighbour. For a while he was just some jerk from across the hall, with a stream of conquests emerging to a walk of shame every morning. But wouldn’t you know? With just a little movie magic and curtains drawn back, his true self is revealed: a thoroughly charming Chris Evans, muscular, topless and yours.

That’s the game right there. It’s why this movie works. A co-star Farris’ equal, whose energy combine with hers to transform the film. Skinny dipping, late-night basketball, and a habit of making the big gestures: in rom-com terms he’s a home run, and what more could a girl ask for? Farris has never seemed happier. It’s like all those years of hoping, praying and believing have finally given her an okay-to-average movie worth fighting for.