Voices of a Distant Star (ほしのこえ Hoshi no Koe, lit. "Voices of a Star") is a Japanese anime OAV by Makoto Shinkai. It chronicles a long-distance relationship between a teenage couple who communicate by sending emails via their mobile phones across interstellar space. The series has been broadcast across Japan by the anime satellite television network, Animax.

Hoshi no Koe was written, directed and produced entirely by Makoto on his Macintosh computer. Makoto and his fiancée provided the voice acting for the working dub. (A second Japanese dub was later created for the DVD release with professional voice actors.) Makoto's friend Tenmon, who had worked with Makoto at his video game company, provided the soundtrack. Shinkai and Tenmon had earlier worked together in the making of Kanojo to Kanojo no Neko ('She and her Cat'). The duo later also collaborated in the 2004 release of The Place Promised in Our Early Days. This half hour OVA also represents the "long distance" relationship between Makoto Shinkai and his wife, as Shinkai spent often long hours in the studio and communicated with his wife via text messaging.

In July 2002, ADV Films announced that they had licensed Hoshi no Koe for U.S. distribution and would release the 30-minute short as "Voices of a Distant Star." The finished DVD premiered in May 2003 at Project A-Kon in Dallas, Texas. The DVD version also includes his earlier work, She and Her Cat.

A middle-school girl named Mikako Nagamine volunteers for the UN Space Army in a war against a group of aliens called the Tarsians, named after the Martian region (Tharsis) where they were first encountered. As a Special Agent, Mikako pilots a giant bipedal robot or mecha as part of a fighting squadron attached to the spacecraft carrier Lysithea.

When the Lysithea leaves Earth to search for the Tarsians with Mikako on board, Mikako's boyfriend Noboru Terao remains behind. The couple continues to communicate across interplanetary, and eventually interstellar space via the e-mail facilities on their mobile phones.

As the Lysithea travels deeper into space, the e-mails take increasingly longer to reach Noboru on Earth, and the time-lag of their correspondence eventually spans years.

The plot loosely resembles the 1975 science-fiction novel The Forever War by Joe Haldeman.

The narrative begins in medias res in 2047. Mikako is apparently alone in a hauntingly empty city, trying to contact people through her cell phone. She finally says, in an empty classroom with stacked chairs, "Noboru? I'm going home, okay?", a rhetorical question which is answered with a busy line on her cell phone. Then she wakes up to discover that she is in her mecha orbiting an alien gas giant. She then goes to a moon or planet in the background, the fictional 4th world of Sirius System, Agartha.

In the middle of the anime proper, she sends an email to Noboru (which shows the date 2047-09-16), with the subject "I am here", saying "to the 24 year old Noboru, from the 15 year old Mikako" (and something else which requires translation) (in reference to time dilation, see below) which would only reach him 8 years, 224 days and 18 hours later, and just hopes it reaches him. Some flashes of imagery, perhaps indicative of memory, a hallucination, or even a mystical encounter, are then shown. (This sequence notably features the only communication in the whole anime with a third character, an eponymous Tarsian, despite the frame story being that of an interstellar war. The other Tarsian killed by Mikkako in close combat, if it is another Tarsian, is the only other character in the entire story.) It is a morphing character that looks like a younger Mikako. While they're speaking however, that character morphs into a Tarsian and then into an older version of herself. The same room where she woke up in the beginning of the animation is presented again, with the same ambience, but this time she is squatting in the corner, sobbing and pleading with her doppleganger to let her see Noboru just once more time to be able to say "I love you" to him.

The other being says "It will be all right. You will see him again". The ship's alarm starts warning her that the Tarsians suddenly coming from everywhere. Mikako cries even more, yelling "I don't understand!". A climactic battle ensues. Meanwhile, back on Earth, Noboru receives the message, albeit almost 9 years in the future. A voice-over dialogue commences between the two of them which functions as a synchronous soliloquy on the same subject. "Meanwhile," back at Agartha, three of the four carriers equipped with the warp engines which brought the expeditionary force to Sirius have been destroyed. The Lysithea is still intact after Mikako joins the fight and stops its destruction. After winning the battle, Mikako lets her damaged mecha drift in space.

Some interpretations concede that Mikako will not return from space, inasmuch as the remnants of her fleet would have jumped through space back to the Earth by the time Noboru receives messages eight years later. Also, headlines in newspapers seen in Noboru's apartment and announcements on board the Lysithea suggest that the means by which the fleet navigated between planets and systems was disrupted somehow and the fleet would have trouble finding it's way back to Earth.

It is possible that Noboru and Mikako were eventually reunited in space as at the end of the film, Noboru joins the space armada and will apparently be part of the second fleet which will continue the search for the Tarsians. However, the latest information on the fleet suffers the same time lag as Mikako's emails so whether the original fleet has survived the last eight years since its final battle in the Sirius system is unknown.

Other versions, including the storylines in the associated manga and novel, have decided that Mikako's spacecraft warped a distance of more than 8 light years from Earth, thus causing the eight year transmission time of the final message. It is implied that Mikako did indeed survive the final battle along with elements of her fleet, but would have to make their way back to Earth through slower means due to the loss of their warp engines.

One reading of the Tarsian's attack is that it is a part of their plan to force humanity's evolution and development through war.

From Wikipedia