Will's out-of-touch approach to teaching Spanish class - including a questionable rendition of "La Cucaracha" in sombrero and serape on Taco Tuesday - prompts some complaints. Principal Figgins then offers some good news and some bad news: a tenured teaching position has opened up at McKinley (something that would serve Will well as he and Emma plan a family), but Will's just one of the potential candidates. He needs to step up his game in the classroom if he wants the job.
Will takes an adult ed class to improve his Spanish skills taught by David Martinez, whose perfectly white teeth prove distracting to his students. Chatting with David after class, Will learns that David has had difficulty finding a job teaching at a high school because of hiring freezes, and when David asks why Will's brushing up his Spanish, Will hesitates to discuss the job opening.
David reveals that he's a former top tooth model in the midst of a career change; he wants to do something more permanently positive than just grinning by teaching kids. David also envies Will's position teaching glee club - he learned English by watching "Solid Gold" and cites studies about how new language skills are retained better when delivered through music. He thinks that getting students to sing in Spanish would get them to learn without even realizing it. Will decides to try to accomplish the same thing with New Directions in hopes of impressing Figgins.
Will walks in on Sue trying to persuade the glee club boys to put their virile teen years to good use by donating to a sperm bank to help fertility challenged women. She tells Will that she was dismayed by the quality of the donors she herself encountered at the sperm bank, and she has chosen to find her own within the halls of McKinley - Sue has decided to have a child.
Will's surprised and somewhat skeptical, but Sue insists that she plans to put her family life above her career for a change before it's too late - especially now that she has her sights set on the tenured position to provided professional security. Sue believes that she's first in line, and as a proven champion has the job locked up, so she instructs Will to provide her with a sample to ensure that her offspring has a full head of hair.
However, Sue is called into Figgins' office, where she learns that complaints have filed against her teaching skills. She finds Figgins entertaining - and possibly enamored of - the school's synchronized swimming team coach, Roz Washington, who has leveled some criticism about the Cheerios' recent failure to capture the championship. Now Roz wants a shot at Sue's job.
Will tells New Directions that his latest lesson will require them to sing only Latin songs or songs by Latin performers. He introduces them to David, who Will has invited to observe and help introduce the concept of duende, a Latin version of soul. By example, David performs LMFAO's "Sexy and I Know It," steaming up the choir room with his moves and attitude.
Sam and Mercedes seek Emma's counseling advice as they try to figure out how to deal with what's going on between them without hurting anyone, including Mercedes' boyfriend Shane. After shocking them with a pamphlet titled "So You're a Two-Timing Ho," Emma suggests that they need to spend some time NOT talking about it. She thinks that all the modern-day distractions of communicating through technology has left teenagers with little time to quietly reflect. Emma wants them to spend a week not speaking so that they can get a clearer idea of what their true feelings are.
After charging up the Cheerios with a high-energy performance filled with modern dance moves, Roz taunts Sue over her "stale, white-bread" approach. Sue tells Roz that she's on to her "All About Eve" routine and has figured out that she plans to swoop in to steal the coaching spot when Sue's on maternity leave. Roz mocks Sue's plans: "You gonna get in those stirrups and you're gonna push and push, and a full-grown adult's going to pop out with a briefcase and a job talking on a cell phone." Roz also says that she doesn't need to steal Sue's job, because Figgins is going to hand it to her: her Olympics bronze medal marks her as the face of the Cheerios future. Now Sue's even more determined to prove Roz wrong.
Rachel, Kurt, and Mercedes watch "Twilight" as Mercedes tries to find some sense in the story of a girl torn between two boys. When Kurt wants to know why the girls are being so serious, Rachel reveals that she's accepted Finn's proposal. Mercedes thinks Rachel's crazy, and Kurt's apoplectic. He wants to know how this affects her plans for NYADA.
Rachel assures them that her and Finn's struggles as a young married couple will simply become a charming part of her backstory when she becomes famous. She knows that Finn is the man for her as surely as she knows she'll be a star. Reluctantly, Mercedes and Kurt agree to keep her secret.
In the glee club room, Mercedes sings a bilingual version of Gloria Estefan's "Don't Want to Lose You" as a not-so-subtle message to Sam without actually speaking to him. The next performance has Sam taking the lead on "Bamboleo" by the Gipsy Kings mashed up with Enrique Iglesias' "Hero," as the rest of the glee club boys back him up dancing in long, pointed-toed Mexican cowboy boots. Sam, too, aims his message directly at Mercedes.
When Will learns that many of the Latin touches were suggested by David, Santana rubs it in by suggesting that David's "the best Spanish teacher ever." She sarcastically suggests that she's excited to see what Will has planned to "defend your Spanish teacher honor."
Emma confronts Sue about the inappropriateness of asking for Will's sperm. As Sue responds with insults, Emma tries to understand why, if Sue hates Will so much, she'd want him to father her child. Sue describes how typically her heart pulsates with a wild, irrational rage - and she never wants her offspring to feel that. Will's always met Sue's challenges with kindness and optimism, and if those qualities are genetic, she wants them for her child. Sue doubts that Will would accept, and Emma leaves it to him to give her an answer, but she tells Sue she thinks having a child would indeed be good for her.
As Finn lifts weights, Kurt presents him with a stack of college brochures, hinting broadly that Finn might find a school in New York. When Finn realizes that Kurt knows about the proposal, Kurt lays into him for not telling him - they're supposed to be brothers. Finn wants to keep the info from Burt for the time being, but Kurt counters the point: "Don't you think something you have to keep from everyone you love might not be the best idea in the first place?" Upset, Finn says that Rachel is the only good thing in his life right now.
While Kurt understands that Finn's had a rough year, he thinks that Finn has the same star potential as Rachel does but just doesn't believe in himself. Kurt thinks Finn should plan on marrying Rachel someday, but he shouldn't just be the guy who holds her purse on the red carpet. Kurt tells Finn that he's unique in the world of the arts, and he shouldn't give up on himself yet. Kurt's words seem to get through to Finn.
Believing that Santana was the student who lodged the complaint against her, a menacing Sue confronts her. Santana insists that she didn't do it, and Will tries to intervene, but Sue blames Santana for putting her "family" at risk. Sue then tells Will that she's found an even better sperm donor.
As Emma admires her own prolific output creating new pamphlets, Will crams to learn more Spanish. She tries to ease his stress by jokingly showing him the pamphlets, but he snaps at her: doesn't she realize he's doing this so he can take care of her? He continues to take his frustrations out on her, causing her to storm off.
In the auditorium, Santana performs a bilingual version of Madonna's "La Isla Bonita" onstage with David, as the students watch. After some more taunts from Santana, Will takes the stage with a full mariachi band, dressed as an authentic matador, singing a Latin-flavored take on Elvis Presley's "A Little Less Conversation" peppered with complicated Spanish lyrics. Upon finishing, Will tells Santana he's realized that she was the student who complained to Figgins about his teaching technique.
Santana points out that his embrace of cultural stereotypes, while acceptable to the students who don't know any better, offend her as a Latina. She forces Will to admit that the reason he became a Spanish teacher was because it was the only position open at the time. She tells him that an amazing teacher once taught her that without passion, you can't succeed - and he is that teacher.
In the teachers' lounge, Coach Beiste sings the praises of Emma's pamphlets, which have finally awakened the football team to the dangers of jock itch. The pamphlet was so successful that the coach's husband ordered thousands of copies for his college team and teams across the Big Ten. Beiste tells Will that he should be proud of Emma, and he agrees that he is.
In the night class, David hands out awards to his students, giving Will the "Most Improved" trophy. Will says that it's not exactly the honor an actual Spanish teacher should receive. He then tells David that he and the glee club students have recommended David to Figgins and the job is his. Overjoyed, David says that his parents were immigrants who had to lie about their citizenship to go to school, and now he's the one teaching it.
Will says that he'll be taking an opening in the history department, and he hopes to find his duende there. David tells him that when Will's teaching glee club, he's got duende coming out of his orejas (ears). Then David wonders who got the tenured position.
Becky gives Sue a fertility injection. As Becky confesses to Sue that she was the one who filed the complaint against her, Sue tells her she already knew ("after 'Tinker, Tailor, Soldier, Spy'-ing my way through Figgins' filing cabinet"). Becky says that she was just worried Sue isn't as focused on the Cheerios as she once was. Sue forgives her because she is being honest. Impending motherhood has given Sue perspective and reignited all her passions, and Becky assures Sue that she'll be a great mom.
Mercedes and Sam encounter each other wordlessly in the halls, but they're interrupted by Shane, who's meeting Mercedes for lunch. She walks off with him, but clearly her heart is still with Sam.
Later, Will presents Emma with an elaborate dinner and a pamphlet he's made himself: "So You Were a Jerk to Your FiancÃ©." A second pamphlet congratulates her: it was Emma who was granted tenure. Will explains that his first marriage ended because his wife didn't believe in him, and he made the same mistake with Emma. He wants to stop the cycle and make sure that Emma realizes that she's as special and amazing as he knows she is.