The movie takes place in New York City and follows the lives of six young adults in their late twenties and early thirties. Sam Wexler, played by Josh Radnor (also the writer and director of the film), is a struggling writer who is trying to get his first book published. One day, on his way to a meeting with a publisher, he encounters a young boy named Rasheen who has been separated from his family on the subway. Sam decides to take Rasheen to his apartment until he can locate his family. This leads to a bond between the two that becomes an important part of the film's plot.
Annie, played by Malin Akerman, is Sam's best friend and roommate. She is an aspiring singer with low self-esteem and a fear of commitment. Annie is constantly searching for validation and attention from men, often leading to failed relationships.
Charlie, played by Pablo Schreiber, and Mary Catherine, played by Zoe Kazan, are a couple who are considering moving to Los Angeles. Their relationship is put to the test when Charlie is offered a great job opportunity on the west coast. Mary Catherine is hesitant to leave New York and her career as a pediatrician, causing tension between the two.
Finally, Mississippi, played by Kate Mara, is a cabaret singer who catches Sam's eye. They begin dating, and Mississippi becomes a valuable part of Sam's life. She helps him to see things in a different light and encourages him to pursue his dreams.
Overall, Happythankyoumoreplease is a heartfelt and charming film about the struggles that young adults face as they try to navigate their way through life and love in the city that never sleeps.