Divorcee Lauren Reynolds (Drew Barrymore), who has two sons named Brendan (Braxton Beckham) and Tyler (Kyle Red Silverstein), meets Jim Friedman (Adam Sandler), a widower with three daughters Hilary (Bella Thorne), Espn (Emma Fuhrmann), and Lou (Alyvia Alyn Lind) on a blind date. The date ends in a disaster due to Jim’s clumsy and careless attitude and Lauren’s perfectionist nature along with the fact that they have their date at Hooters.
The next day at work Lauren talks about her experience to her friend Jen (Wendi McLendon-Covey) who reassures her by saying that everyone has a bad blind date and asks who set the date up to which Lauren replies that it was the mother of one of Tyler’s classmates. Jen then suggests to Lauren that she try on a black dress, which Lauren does, causing Jen to remark that she looks better than expected. Lauren tearfully begins lamenting that she should have tried dressing better when she was married to her ex-husband. This causes Jen to assert that her (Lauren’s) ex is a pig and a concerned Lauren states that even her children are unaware of their father’s irresponsibility.
Meanwhile, Jim discusses his date with his co-worker, commenting that Lauren dressed like a principal which made him feel like he was more on a detention than a date. He declares that he’d rather spend his time with his daughters than date again. When Hilary makes an appearance Jim affectionately calls her Larry which annoys her since people mistake her for a boy due to her tomboyish looks. Jim proposes a camping trip with family which Hilary opposes saying that her classmates are visiting places like Florida and Switzerland. Jim responds by saying that they don’t have enough money to afford such a trip to which an upset Hilary agrees and wistfully expresses that they could one day go someplace.
Later, Jim and Lauren run into each other at a pharmacy where Jim looks for tampons for his daughter Hilary and Lauren searches for an erotic centrefold for Brendan because she accidentally destroyed his original that she found underneath his bed. After their encounter, Jim realizes that their credit cards were mixed up due to their exchanging their purchased items to avoid embarrassment, and goes to Lauren’s house to switch them back. There, he and Lauren learn that Jen has broken up with her boyfriend Dick (Dan Patrick), who happens to be Jim’s boss, over his having kids, and that they will no longer be going on a planned African vacation together. Unbeknownst to each other, Jim and Lauren both arrange to go on the pre-booked vacation with their families. When they arrive in Africa the two families are surprised to see each other. Things get more awkward when Jim and Lauren are given a romantic suite.
The families are put together for a “blended familymoon”, where they get together with other couples, including the oversexed Eddy (Kevin Nealon) and Ginger (Jessica Lowe), Eddy’s new bride and quite his junior to the chagrin of their teenage son Jake (Zak Henri), who Hilary develops a crush on at first sight.
The kids make an awkward impression with each other, with Brendan calling his mom “hot,” and the others not knowing how to react to Espn acting like her imaginary mom is there with her as she is not ready to let go of her quite yet. Over time though, they begin to bond with each other and each other’s parents.
Jim makes the boys happy by helping them with adventurous sports and they slowly warm up to him, ultimately seeing him as a father figure they needed, while Lauren takes care of the girls, and helps Hilary to change her tomboyish look into a more feminine one drawing the attention of her now boyfriend, Jake. Jim is pleasantly surprised by her change of appearance and he and Lauren begin to warm up to each other as time passes. They inadvertently get together for a couples massage and have fun with each other. Afterwards, the girls prove their affection for Lauren, when Lou asks for her to put her to bed. Lauren does so and sings “Somewhere Over the Rainbow,” which, unknown to her, was the song Lou’s mom used to sing. The other girls pretend to sleep, while realizing how much they truly love Lauren. She returns this feeling when she maternally kisses each girl’s forehead as she says goodnight. Jim starts to realize the depth of his feelings for Lauren.
On the last night of the trip, Lauren puts on a beautiful black dress that she admired earlier. She wears it that evening and receives admiration from everyone. While the children are pulled away for a kids-only buffet, Jake briefly smiles at Ginger, earning her tearfully telling Eddy how truly happy she is, while they agree that they are ultimately going to be a beautiful family. Meanwhile, Jim and Lauren are sat down for a romantic dinner, which Lauren soon discovers was actually planned by Jim specifically for her. They chat briefly about basic parenting techniques and then pull in for a kiss; however, at the last second, Jim pulls away, apologizing and explaining that he “can’t do it”.
After returning home, Jim realizes he misses Lauren and that he’s fallen in love with her, which he admits to his daughters who are ecstatic with the news. Although Espn is not fully ready to move on from her mother’s passing, she also doesn’t want her dad, or herself to lose Lauren. She starts to move on by telling her dad that her mom said that she had other things to do in Heaven and wouldn’t be around as much (and of course to increase her allowance). At the kids’ behest, Jim goes to Lauren’s house to give her flowers, only to find her ex-husband Mark there, pretending to be back with Lauren. Tyler gets excited to see Jim and wants to play ball, but Jim sadly leaves and Mark bails on his son again. Mark later tries to make a move on Lauren, but she refuses since he has continuously failed to be a good father, as well as having an affair with his receptionist during their marriage.
That following Saturday, Lauren and Brendan go to support Tyler at his game, along with Jen, Dick, who Jen has worked things out with, and his kids. Mark, once again, is a no-show. Jim and his daughters arrive to show encouragement, inspiring Tyler to hit the ball. Jim then finds Lauren and they admit to wanting to be together, and they finally kiss, to the happiness of their kids, who realize that they are already a family.