In 1910, when Howards End was published, the world was just beginning to be shaken by the First World War. Yet, despite this, the novel offers an unwavering faith in people's ability to get along and form strong bonds, even in a rapidly changing society. Likewise, the play borrows from this theme, as does the house itself, which acts as a microcosm of the country.

The Schlegel sisters befriend Leonard Bast, an impoverished clerk who lives with Jacky, a woman of dubious origins. The sisters pass along advice from Henry that the insurance company where Leonard works is headed for bankruptcy. He quits, settling for a much lower-paying job. He is devastated, and soon he discovers that his wife, Helen, is pregnant. Henry, overwhelmed by guilt, honors Ruth Wilcox's dying request that she leave Howards End to Margaret. He also stipulates that the inheritance will pass to the son of Helen and Leonard.

When Helen visits the estate with an impoverished Leonard and Jacky, she reveals that she considers Henry responsible for their plight. He denies responsibility, but when Jacky drunkenly reveals that she was his former mistress years ago, he realizes he must offer help. He reluctantly sends the first check to the family, but returns it out of pride. Fearing the Basts will be penniless, Helen instructs her brother Tibby to give them more money, but Leonard declines further assistance. Ultimately, the Schlegels forgive him. Tibby, meanwhile, has a falling out with his girlfriend.