It was the only Ghibli film not directed by Miyazaki or Takahata for seven years until The Cat Returns was released in 2002, which focused on a minor character of the film, Baron.
Shizuku Tsukishima is a 14-year-old student at Mukaihara Junior High School, where she is best friends with Yuko Harada. Living in Tokyo with her parents Asako and Seiya, as well as her older sister Shiho, Shizuku is a bookworm and is keen on writing. During an ordinary evening, she looks through the checkout cards in her library books. She discovers they have been checked out by Seiji Amasawa (天沢 聖司). Over the next few days, Shizuku encounters a young man, later revealed to be Seiji, who often annoys her.
Finding a cat riding a train, Shizuku follows it to discover an antique shop run by Shiro Nishi. In the shop is a cat statuette, "The Baron". After Shizuku returns home, she learns from Yuko that Sugimura has inadvertently upset her, as he does not know that Yuko likes him and instead had a crush on Shizuku. Sugimura's actions cause an argument with Shizuku, and she turns him down.
At the antique shop, Shizuku sings "Take Me Home, Country Roads", a song she has been translating for her school graduation, accompanied by Seiji and Nishi. Seiji is revealed to be the grandson of Nishi, and Shizuku and Seiji befriend each other. Seiji is learning to make violins to follow his dream as a master luthier. Days after the two meet, Seiji leaves for Cremona, Italy, for a two-month study with a master violin-maker. Firming her resolve, Shizuku decides to test her talents as well. Discussing with Yuko, she decides to pursue her writing seriously during the two months. She asks Nishi if she can write about The Baron, to which Nishi grants his consent on the condition that he will be the first to read the finished story.
Shizuku begins to concoct a fantasy story featuring herself as the female protagonist, the Baron as the male hero who is looking for his lost love, Louise, and the cat she followed from the train (who is, among other names, known as "Moon" and "Muta") as the story's villain who took her from him. Devoting her time to her writing, Shizuku eats snacks, stays up until early in the morning, and her school grades drop. Shizuku argues with her family over her grades, and as she continues to push herself into finishing the story before Seiji returns, she begins to lose heart.
When her story is complete, Shizuku delivers the manuscript to Nishi. After Nishi reads Shizuku's writing and gives her his benevolent assessment, she breaks down in tears as the stress of the last two months finally turns into relief. Consoling her with udon, Nishi reveals to Shizuku that when he studied in Germany in his youth, he found his first love, Louise. They discovered the twin statuettes of the Baron and his female companion in a cafe, but they could only purchase them singly because the female statuette was in repair at that time. Nishi kept the Baron while Louise would hold onto the Baron's companion, and they and the two cat statuettes would reunite at a later time. However, the two lovers and the statues were subsequently separated during World War II and were never reunited.
Deciding she wants to attend high school to learn more about writing, Shizuku is returned home by Nishi and announces to her mother that she will return to studying for her entrance exams full-time. The next morning, she discovers Seiji below on his bicycle. He has returned a day early, and decided to finish high school before returning to Cremona to become a luthier.
The two ride Seiji's bike to a lookout and watch the sun rise over the city. While they are there, Seiji professes his love for Shizuku and proposes future marriage, and she happily accepts.
Whisper of the Heart was based on the manga Mimi o Sumaseba which was originally created by Aoi Hiiragi. The manga was serialized in Shueisha's shōjo manga magazine Ribon between August and November 1989, and a single tankōbon volume was released in February 1990. The volume was reprinted on July 15, 2005. A second manga by the same author titled Mimi o Sumaseba: Shiawase na Jikan was serialized in Shueisha's Ribon Original in 1995. A spiritual sequel to this film adaption, The Cat Returns, was turned back into a manga by Aoi Hiiragi, under the name Baron: Neko no Danshaku.
During production, the backgrounds in the fantasy sequences of the film were drawn by Naohisa Inoue and the woodcut of the imprisoned violin-maker was created by Miyazaki's son Keisuke Miyazaki, a professional engraver. Japanese musical duo Chage and Aska's short music video, titled "On Your Mark", by Studio Ghibli was released along with Whisper of the Heart.
The film score of Whisper of the Heart was composed by Yuji Nomi. At times during the film, Shizuku translates John Denver's song "Take Me Home, Country Roads" to Japanese for her school's chorus club. She writes her own humorous Japanese version of the song, called "Concrete Road," about her hometown in western Tokyo. The songs were actually translated by producer Toshio Suzuki's daughter Mamiko with Hayao Miyazaki writing supplemental lyrics. These songs play a role at points in the story. A recording of "Take Me Home, Country Roads," performed by Olivia Newton-John, plays during the film's opening sequence. The song was also performed by Shizuku's voice actress Yoko Honna.
Whisper of the Heart was the first Japanese film to use the Dolby Digital sound format. An English dub of this film was released by Walt Disney Home Entertainment on March 7, 2006. Turner Classic Movies televised both the dubbed and subbed versions on January 19, 2006 as part of their month-long celebration of Miyazaki in honor of his birthday, January 5. The English title, Whisper of the Heart, was created by Studio Ghibli and used on several officially licensed "character goods" released around the same time as the film was released in theaters in Japan. The North American Blu-ray was released on May 22, 2012, alongside Castle in the Sky and The Secret World of Arrietty. GKIDS will re-issue the movie on Blu-ray & DVD under a new deal with Studio Ghibli.
Whisper of the Heart was the highest-grossing Japanese film on the domestic market in 1995, earning ¥1.85 billion in distribution income. Whisper of the Heart received very positive reviews from film critics. It has an 91% approval rating on review aggregator Rotten Tomatoes, based on 11 reviews. Time Out London included Whisper of the Heart in their Top 50 Animated Film list. It was also included in Film4's Top 25 Animated Film list. On Anime News Network, Michael Toole gave it an overall grade of A-, calling it "beautiful and evocative; a fine tale of adolescent yearning and aspiration."
General producer and screenwriter Hayao Miyazaki defended the film's ending, saying that it was his idea. Miyazaki wanted Shizuku and Seiji to "commit to something."
Over the course of the film, Shizuku is working on a fantasy novel that revolves around a cat figurine, named The Baron, which she discovers in Mr. Nishi's antique store. In 2002, Studio Ghibli produced a spin-off film The Cat Returns, directed by Hiroyuki Morita and again featuring The Baron, and the stray cat, Muta, in the film. Later on, Muta and the crow (Toto, who is friends with him and the Baron) seem to appear in The Secret World of Arrietty as two skirmishing animals.