The film depicts the crossing of the Inner German border by the Strelzyk and Wetzel families from the GDR to West Germany with a self-made hot-air balloon in 1979.

The two families, including four children, successfully floated across the sky from Pößneck, Thuringia to Naila, Bavaria, then situated 8 kilometres (5.0 mi) south of the Iron Curtain.

[2] Before making the film, Herbig was allowed to inspect the thousands of pages thick file about the balloon flight belonging to the Stasi, the former secret service of the GDR.

The Strelzyk and Wetzel families develop a daring plan to flee the GDR to West Germany in a self-made hot air balloon.

Their teenage son Frank has fallen in love with Klara Baumann, the daughter of his neighbour Erik, who works for the Stasi, and writes her a farewell letter.

However, the balloon goes down with Doris, Peter, and their two sons Frank and Andreas (called "Fitscher") in the gondola shortly before the border because the pipes from the gas bottles to the burner freeze up and become clogged.

The Stasi finds the abandoned balloon and discovers the attempted escape, and under the direction of Lieutenant Colonel Seidel, begins a large investigation.

Doris in particular is worried because she lost her medication in the forest, which gave the Stasi important information in the form of personalised pills.

Since they must be careful in obtaining the materials to avoid raising suspicion, the family members only buy small quantities of suitable fabric in different cities.

Just as Doris feared, the investigators trace their medication back to the local pharmacy, where all recipients of the tablets are now being identified and checked.

Ten years later, Doris and Peter Strelzyk watch Hans-Dietrich Genscher's announcement from the Prague embassy on television that the GDR citizens gathered there are allowed to leave.

[4] Herbig stated that an attempt had been made to acquire the remake rights, and it had turned out that both families had sold their story "skin and hair".

[10] In NDR Info, Krischan Koch explains that Herbig strives for authenticity down to the smallest details in his film.

[11] Norbert Koch-Klaucke also noted in the Berliner Zeitung that after the successful escape, real-life wrote a completely different script for the two families, which the film does not show: "A new drama begins.

After the successful escape, which made headlines in the West and embarrassed the GDR worldwide, the two families are now feeling the vengeance of the SED state.

Sidney Schering from Quotenmeter.de wrote that the music of Herbig's main composer contributes in part to the fact that Ballon develops such an enormous tension.

The site's critical consensus reads, "Balloon isn't as exciting as the real-life story that inspired it, but it remains a solidly made and often engrossing political thriller.

Andre Petzer from Epd Film says that though Michael Herbig takes dramaturgical liberties when he reduces the three escape attempts to two and condenses the long tinkering with the second balloon to six weeks, he manages to create very emotional moments.

The reasoning states: "Herbig stages the cat and mouse game between the Strelzyk family and the investigator Seidel like a crime thriller and especially towards the end with breathless tension.

The music perfectly supports the drama of the situation, the setting, the equipment and the costumes leave no doubt about the high research effort and the attention to detail.

That makes Balloon a highly exciting, precisely staged and differentiated film about the unattainable desire for freedom – which came true.