[[quoteright:300:http://static.tvtropes.org/pmwiki/pub/images/the_switch.jpg]]
[[caption-width-right:300:Best friend. Surprise sperm donor. What can go wrong?]]

A 2010 comedy film written by Allen Loeb, directed by Will Speck and Josh Gordon, and starring Creator/JenniferAniston, Creator/JasonBateman, and Creator/JeffGoldblum.

Kassie Larson and Wally Mars have been best friends for years. Kassie, after years of bad experiences in dating, has decided to become a single mother through artificial insemination, much to Wally's protests. Nevertheless, she invites him to the insemination party wherein he gets drunk, accidentally spills the collection vial, and decides to replace the sample with one of his own. He blacks out and wakes up with no memory of this. Kassie leaves town, seven years pass, Kassie returns with her son Sebastian, and HilarityEnsues.

Not to be confused with the comedy ''Film/Switch1991'' or ''Film/Switch2011''.

-----
!!This film provides examples of:

* BookEnds: Wally's voiceover and discussion regarding the "human race".
--> '''Wally Mars''': Look at us. Running around, always rushed, always late. I guess that's why they call it the human race. What we crave most in this world is connection. For some people it happens at first site. It's when you know, you know. It's fate working its magic. And that's great for them. They get to live in a pop song; ride the express train. But that's not the way it really works. For the rest of us it's a bit less romantic. It's complicated and it's messy. It's about horrible timing and fumbled opportunities. And not being able to say what you need to say when you need to say it. At least, that's the way it was for me.\\
...\\
'''Wally Mars''': Every once in a while, out of all the randomness, something unexpected happens that pushes us all forward. And the truth is, what I'm struggling to think, and what I'm struggling to feel, is that maybe the human race isn't a race at all.
* [[ChekhovsGun Chekhov's Trait]]:
** Early in the course of the movie, Wally is shown to moan when eating good food. Later, Sebastian is shown to do the same.
** One surprisingly missed by the participants of the movie. Kassie and her sperm-donor have blue eyes and blonde hair. Sebastian has brown eyes and brown hair.
* DisposableFiance: Averted. Roland seems like a genuinely nice guy who just has the bad luck to come up against a Hollywood Romance. (On the other hand, he didn't listen at all to Sebastian's desire to back out of rock climbing.)
* DoggedNiceGuy: To some degree, Wally from the beginning of the movie on.
* DuelingMovies: Filmed and released at the same time as ''The Back-up Plan'', also about artificial insemination and the complications of relationships with the sperm donor.
* ShotgunWedding: [[spoiler: Cassie and Wally in the end.]]
* ThePictureCameWithTheFrame: Sebastian asks for picture frames as gifts, and uses the stock pictures to create his father's family.
* TrailersAlwaysLie: At least some trailers for the film tried to push the idea that Creator/JenniferAniston was the lead character; she's certainly important but it's pretty obvious Jason Bateman is the real protagonist.
* VisualPun: The sperm donor is made to wear a [[HornyVikings Horny Viking]] helmet during the insemination party.
----