[10][11][12] In 2016, Alvarez wrote, produced, directed and starred in the five-part web comedy series The Gay and Wondrous Life of Caleb Gallo.
[13][14] He has performed roles in several television shows including: Will & Grace, Life in Pieces, Jane the Virgin, and Go-Go Boy Interrupted.
[18] From 2018 - 2020, Alvarez played the recurring role of Estéfan Gloria, Jack McFarland's fiancé and later husband, in all three seasons of the 2010s revival of NBC's Will & Grace.
[21] Alvarez has gained prominence for his viral videos on Instagram and TikTok, in which he often portrays a rotating cast of absurdist characters using thick accents and distorting facial filters.
[22] In September 2023, he posted a video featuring his character TJ Mack performing an improvised song titled "Sitting", which quickly became an online sensation, accumulating millions of views and being remixed and covered by fans in various genres.
[23][24][25] Versions of "Sitting" have appeared on the radio in both the United States and Australia, and Vanity Fair has described it as possibly 2023's "song of the summer.
Simms had been impressed after watching old episodes of The Gay and Wondrous Life of Caleb Gallo and asked Alvarez to creative a TV show.
Having grown up in a blue dot in a red state (Tennessee), he thought setting the show in the suburbs of Austin, Texas would be fertile ground for having all types of characters and opinions, saying "There's no set of opinions you can really avoid in a public high school, so I knew all of that in one place could make for good comedy.
Alvarez created the series and stars as the protagonist, an English teacher working at a high school in Austin, Texas.
"[39] He almost didn't graduate college due to alcohol and drug use and got sober because "he was scared not knowing if he was going to be as successful as he knew he wanted to be.
"[39] While a student at University of Southern California, Alvarez allegedly stalked a female friend's boyfriend who later filed a no-contact order against him.
[43] The following month, the day before English Teacher's premiere, Ebeling filed a sexual assault report against Alvarez with the Los Angeles Police Department for the 2016 incident, which Vulture covered in a December 2024 story.