Walden reconnects with Kate and is sure she’s “The One” – that is, until he meets Vivian and becomes convinced she’s “The One.” Meanwhile, Alan and Gretchen grow closer.
Walden and Kate are together at his house until she gets a call from her partner in China, prompting her to leave for San Francisco, but promising to return to stay with Walden for a few more days. Later, Barry and Jenny go the movies, leaving Walden alone after she tells Walden not to think every women he meets is "The One". Walden talks to Charlie's ashes, asking for advice, but drops it when startled by Vivian (Mila Kunis) knocking on his deck's door.
Meanwhile, Alan and Gretchen are at Barry's apartment, and Alan asks her to move in with him. Back to Walden's, he lets Vivian in and offers to refill her water bottle with filtered water from the kitchen, and is smitten by her looks. In Barry's apartment, Gretchen picks up Alan's wallet to pay for a pizza they ordered, and sees his ID, accidentally learning his true identity.
Vivian and Walden are eating Chinese food and talking about crazy actresses. Vivian starts talking about the many things she did while traveling across the world. Walden begins to imagine traveling together with Vivian (and Alan), and is brought back into reality by Vivian asking which fortune cookie he wants, with Walden replying that he wants both, actually talking about her and Kate.
Alan tells the whole truth to Gretchen, including the reason why he assumed the identity of Jeff Strongman, and his previous relationship with Lyndsey. Gretchen breaks up with Alan and immediately leaves the apartment, to which Alan begs her to come back, saying she has the pizza coupon.
Vivian, having slept at Walden's, wakes up to find him turning his computer desk around so he can face the ocean. She prepares to leave, but Walden asks her to stay a little bit longer, to which she refuses. She asks if he's going to be okay, and Walden imagines her wearing a wedding dress.
Alan is packing up his things to leave Barry's apartment, but before he does, Gretchen comes back, and Alan immediately starts apologizing and saying his feelings for her are real. Gretchen says she wants to break up with Jeff Strongman, and get to know Alan Harper. She then asks for a final moment with Jeff, and kicks him in the testicles, asking if "Alan" is okay afterwards.
Back at Walden's, Kate returns and tells him she arranged to get a few extra days with him, and also that she took her underwear off at the car, throwing her panties at Walden's face. He tells Kate that he met someone while she was away, and he doesn't know what he wants, wanting to pursue it in order to be sure. She kicks him in the testicles and leaves. Walden then goes looking for Vivian and finds her setting up a camping tent. He pats her in the back and gets kicked in the testicles again. Vivian asks what he is doing there, and he replies that he gave up the idea of asking Kate to marry him because he couldn't stop thinking about Vivian. She correctly deduces that Walden is the kind of guy that falls in love easily, and tells him to go home. Walden then is seen daydreaming about Kate and Vivian kissing while he watches, but Alan and Barry, who are sitting next to him, think that Walden asked them to kiss, and lean over to do it, saying that "it is his house".
This is the first episode that Walden talks to Charlie. (his ashes in the urn)
This episode marks Brooke D'Orsay's last appearance in the series.
At the time of this episode, Mila Kunis (Vivian) and Ashton Kutcher (Walden) were engaged and expecting a baby together- making Walden's instant attraction to Vivian all the more ironic. Mila and Ashton's daughter Wyatt was born on October 1st, 2014.
Several jokes were made by Vivian referencing highlights of Mila Kunis' acting career. When Walden compliments her name, Vivian claims her mother got it from "That '70's Show" (which Mila Kunis and Ashton Kutcher co-starred in, also portraying love interests) although the show she references is Maude. Another joke comes when Walden suggests Vivian should not go out into the pouring rain again; Vivian laughingly says, "It's just a little water! It's not like I'm gonna melt- I'm not the Wicked Witch of the West!" This references Mila's 2013 role in Oz the Great and Powerful as Theodora, who gradually transforms into the Wicked Witch during the film.
Another joke made by Vivian was when she camps in the woods and Walden goes after and when Walden claims he doesn't know the way home and he should stay with Vivian, she picks up the car keys from the ground, unlocks the car and says "Dude, there's your car". This references Ashton Kutcher's line in 2000 movie "Dude Where's My Car".
Charlie's urn is dropped for the fourth time in this episode (He should be of China descent instead of Irish descent, in the episode title).
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