Trama

Newlywed couple Nat and Josh are deliriously happy despite their differences, though friends and family aren't convinced that they can last. With their first anniversary approaching and attractive alternatives in the mix, can they last?

After a seven month long passion-filled courtship, thirty-something Londoners Natasha Redford and Josh Moss get married despite they being mismatched in personality and temperament, something that their closest friends and family members can see - some who predict the marriage won't last a year - even if Nat and Josh themselves don't see it. Nat, a marketing company manager, is more professional and controlled. Josh, a novelist with a current case of writer's block, is more carefree and childlike. Nine months into their marriage, Nat and Josh have their first session with arguably the most distracted marriage counselor in the city, that session which may be the deciding factor in whether they continue in being husband and wife to each other. Their issues over the preceding nine months are told in flashback, and include little idiosyncrasies which annoy the other, and tensions with each's in-laws, beyond the general differences in their personalities. But what may be the biggest threat to a happily-ever-after for them as a couple may be temptations with others to who, at least on paper, each is more well suited. For Nat, that temptation is client Guy Harrap, an American manufacturer who, unknown to Nat, hired her firm solely in his personal attraction to her. For Josh, that temptation is his old girlfriend Chloe, an aide worker who only recently reentered his life after a four year stint away working in Africa, the two of them in theory never having really broken up in the first place.—Huggo

Ambitious high-flyer Nat (Rose Byrne) and struggling writer Josh (Rafe Spall) fall in love at first sight at a party. After 6 months they decide to marry. Their wedding goes as planned despite many friends' comments that the marriage will not last, an embarrassing best man's speech, and a coughing priest.

When Nat returns to work after the honeymoon, she's embarrassed when Josh calls her during an important conversation to tell her she is sexy and that he misses her. Later, the two meet with their solicitor to discuss how to handle medical crises (last wishes). Josh told her the wrong time to be there, and thanks to his trickery she actually turned up early.

The couple throw a dinner party to use their wedding gifts. Some of their differences are highlighted when they talk about their honeymoon. When the topic changes to Josh's former flame Chloe, Nat discovers that the two never officially broke up when she departed for 4 years in Africa. The women talk about the constrictions of marriage. Nat's sister Naomi has issues with her own husband's annoying habits. Josh's best man Dan asks Chloe out after hinting at sexual advances.

The following day, Nat and her co-workers make fun of their new client, Guy Harrap. They believe he will be a stereotypical American who thinks the British are "quaint". They do not realize that their client has been sitting right there in the same cafe. Before the meeting, one co-worker steals Nat's wedding ring, believing that the account will have a better chance of success if she appears single. During the meeting, Guy, deliberately fulfills their expectations of him: speaking in a brash American way. Then when they focus on business talk, he switches to his true self, embarrassing the women for their earlier stereotyping. Nat apologizes. Feeling the attraction between them, she ends up leaving without telling him.

Josh invites Chloe to dinner because Nat's going to a work party that night. Chloe declines, saying she's going out with Charlie, whom she's been dating recently. Nat receives a large bouquet of roses from Guy. The couple face difficulties dealing with the small differences in their way of living: Josh leaving the toilet seat up, Nat's inability to sing the right words to popular songs, different definitions of the rubbish bin being full. Guy shows Nat around one of the factories he owns, where one of his longest-serving workers expresses approval of her.

Nat tries to discourage Josh from accompanying her to a work party, but he is determined. Unfortunately, he makes a fool of himself with embarrassing dancing, and standing next to a poster he can joke about during the night. When he approaches Nat while she's talking with Guy, she still doesn't reveal that he is her husband, and Guy attempts to shake him off, assuming he's an unwanted menace. Guy asks her to dinner and Nat declines.

Meanwhile, Chloe and Charlie attend a boring dinner party, then leave early to adjourn to Charlie's apartment. As they kiss on the bed, Chloe's co-worker Alexandra joins them, and Chloe finds herself in an awkward threesome. The next morning, she calls Josh to tell him about it, and he soon turns up at her apartment with coffee and her favorite sweets to cheer her up.

Chloe and Josh then go Christmas-shopping. They end up at a lingerie shop with Josh uncomfortably trying to make conversation with the shop assistant among the shop's expensive contents. When Nat meets with Guy at his hotel to discuss their business deal, she refuses several times to go to his actual hotel room. He mentions that he has booked a conference room down the hall, but when Nat enters, she finds a romantic dinner complete with doves and a violinist. She finally blurts out that she's married and can't leave her husband because it would destroy him. She manages to remove herself from Guy and his offer of a relationship.

Back at the lingerie shop, Chloe calls Josh into her dressing room to help her with a caught hook and while he's assisting her, they venture into a kiss. Chloe apologizes in turn, and Josh buys the lingerie she tried on for Nat. There is crosscutting between Nat and Guy and Chloe and Josh on separate streets until they meet at the corner for an uncomfortable exchange. Josh suggests that Chloe and Guy get together; Guy proposes that the four of them go out together.

A Christmas game of charades illuminates this: trying to mime "Doctor Quinn Medicine Woman", Josh embarrassingly relating the word "Quinn" to "quim" and offends Nat's grandmother by thrusting his arms at the groins of the women in the room. Josh says that Nat's stepfather made him sleep in a small bunk bed as "punishment" for this. Nat retaliates that her sleep was no better at his parents' house, thanks to what she was forced to overhear above the room in which she was placed.

Josh claims that Nat's parents have a clearly negative view of him, giving him books titled "How to be a Successful Writer" and "Stop Wasting Your Life". An awkward scene in which sexual photos are intermingled with pictures of the couple's honeymoon being displayed on their newly gifted digital photo frame. Josh unsuccessfully attempts to stop Nat's parents from seeing the images. Leaving her parents' house, Nat confronts Naomi about why she stays with her husband; they clearly hate each other. She says that they both "embrace the hatred" and that's what marriage is about.

Nat and Josh have a conversation about his suggestion of Chloe dating Guy. The four meet for dinner and spend the evening playing pool. Chloe and Guy seem to hit it off, happily competing against Nat and Josh. They leave the bar, and Nat asks Guy to talk about packaging details, intending to meet Josh back at their flat afterwards. Chloe and Josh depart together, while Nat and Guy go the other direction. After a moment, Nat passionately kisses Guy, resulting in the ripping of the underwear bought for her by Josh.

Meanwhile, Josh attempts to discourage Chloe's attraction to Guy, and she confronts him about the difficulty with them seeing one another. She admits she is still in love with him and then leaves in a taxi, insistent that they cannot see each other anymore. When Nat returns home, she and he husband talk about their relationship. After 9 months, they decide to get help instead of giving up on their marriage.

The couple then put up with each other's quirks over the next few months, eventually making it to their anniversary. Nat brings out the same expensive lingerie for the special occasion and struggles to do it up because of two broken hooks. Josh leaves the flat, telling Nat he's remembered he has to do something and that he will meet her at the restaurant. He races to Chloe's apartment, only to find that she is heading off in a cab with Guy, whom she embraces lovingly. Nat is meanwhile contemplating phoning Guy. She then decides to go to the restaurant, where her friends and family are there waiting to surprise the couple. After failing to contact her husband, Nat sits down. She discovers that her friends didn't think her marriage would last.

Josh makes it to the restaurant party and tells Nat that he thinks she is the perfect wife, but just not for him. He asks her for a divorce, and she immediately and delightedly agrees. The couple rejoice at the situation, and immediately leave the party to pursue their love interests.

Meanwhile, Guy and Chloe are at the train station waiting to go to Paris on a romantic trip. Josh finds them and professes his love for Chloe. When it's discovered that he split up with Nat, the two are shocked. Nat appears behind Josh, obviously heading for Guy, but Josh awkwardly assumes he is the one she wants to speak to. After a short exchange they happily discuss how perfect Guy and Chloe are for them. In the end, Chloe and Guy mutually break up. Nat ends up kissing Guy and Chloe shares a kiss with Josh.