<P> The show depicts the everyday life of a Cuban - American family with each character finding their own journey . Following the story of Penelope Alvarez (Justina Machado) a United States Army Nurse Corps veteran, facing her return to civilian life with a lot of unresolved issues from her time in the Army . She works as a nurse in the office of Dr. Leslie Berkowitz (Stephen Tobolowsky). After her husband's alcoholism due to post-traumatic stress disorder from his time in the Army make it, in Penelope's words,' unsafe to be in the house', she separates from Victor (James Martínez), taking the children with her . With the help of her Mother, Lydia (Rita Moreno), a refugee who left Cuba as a teen following Fidel Castro's rise to power, she is raising her two children: Elena (Isabella Gómez) and Alex (Marcel Ruiz). Apart from planning her daughter's quinceañera, Penelope starts dating and finds a love interest . Elena, resistant to have a quinces, starts dating a teenager from her class; to later realize that she is a lesbian . After struggling in ways to tell her family about her sexuality she finds the right time to come out . Alex starts working in a school project about Cuba with the help of Schneider (Todd Grinnell) and Lydia . Lydia talks about leaving Cuba escaping from Castro's dictatorship and how she fell in love with her late husband Berto (Tony Plana). </P> <P> Each episode of the series focuses on important issues that face the Hispanic community and families in general . It has dealt with topics such as veterans' struggles with PTSD, depression, and anxiety, as well as sexuality, gender identity, sexism, and religion, amongst others . </P> <Ul> <Li> Justina Machado as Penelope Riera Alvarez, a United States Army Nurse Corps and mother of Alex and Elena . She works as a nurse for Dr. Leslie Berkowitz . After coming back from army service, she joins a therapy group to help her with her depression and anxiety . In the first season she separates from her husband Victor and starts dating Ben . Later she breaks up with Ben after Victor's visit for Elena's quinceañera . In season two Penelope decides to go back to school to become a nurse practitioner . She begins dating an Army Veteran, now EMT Max Ferraro, but breaks up with him after finding out he wanted children of his own, and decides to let him find that chance with someone else, as she believes that she is too old for another child, and has two children of her own . </Li> <Li> Todd Grinnell as Dwayne Schneider, the rich landlord of the building . He is a close friend of the family and Penelope's best friend . Schneider is frequently having one - night stands with different women . Often in the series he talks about having multiple stepmothers and how dysfunctional his family was, while also occasionally discussing his history of addictions . He is Canadian and after years of having a green card decides to become a US citizen . </Li> <Li> Isabella Gomez as Elena Maria Alvarez Riera Calderón Leytevidal Inclán, the activist and feminist teenage daughter of Penelope . After dating Josh, a classmate, and watching gay porn, she discovers that she is a lesbian and comes out to her family . The news doesn't sit well with her father, which upsets Elena . In season two she finds a love interest and founds a Gay - Straight Alliance club at her Catholic School . </Li> <Li> Marcel Ruiz as Alejandro "Alex" Alberto Alvarez Riera Calderon Leytevidal Inclan, the son of Penelope . He wants to gain popularity at school and is part of the baseball team . He starts a school project about Cuba . In season two he begins working during the summer at Dr. Berkowitz's office . </Li> <Li> Rita Moreno as Lydia Riera, a faithful Cuban, Penelope's mother and grandmother of Elena and Alex. She fled Cuba after Castro seized power . She was a dancer and a performer back in the day . Over the course of the season, she develops a relationship with Dr. Berkowitz . </Li> <Li> Stephen Tobolowsky as Dr. Leslie Berkowitz, Penelope's boss and Lydia's love interest . </Li> </Ul> <Li> Justina Machado as Penelope Riera Alvarez, a United States Army Nurse Corps and mother of Alex and Elena . She works as a nurse for Dr. Leslie Berkowitz . After coming back from army service, she joins a therapy group to help her with her depression and anxiety . In the first season she separates from her husband Victor and starts dating Ben . Later she breaks up with Ben after Victor's visit for Elena's quinceañera . In season two Penelope decides to go back to school to become a nurse practitioner . She begins dating an Army Veteran, now EMT Max Ferraro, but breaks up with him after finding out he wanted children of his own, and decides to let him find that chance with someone else, as she believes that she is too old for another child, and has two children of her own . </Li>

Who plays penelope on one day at a time