Strike Witches fans, rejoice, the 501st Joint Fighter Wing is back for the new season, Strike Witches: Road to Berlin! It's been over a decade since the Strike Witches series began, and over the years it has published numerous manga series, light novels, video games and aired a few spinoff shows as well. Let's recap what you need to know to watch this fanservice-filled series.
Strike Witches Season 1
Strike Witches takes place during an alternate World War II. Aliens called "Neuroi" appeared from the sky, causing mass destruction and societal upheaval. The only way to kill these monsters is with the magical power of the Witches, soldiers who strap into Striker Units, transforming their legs into propeller planes. Each Witch, with their animal ears, unique magical abilities and pants-free dress code, is tasked to save humanity from destruction.
The series' protagonist is on Yoshika Miyafuji, a seemingly average girl with some hidden talents, namely her magical healing abilities, which a member of the 501st Joint Fighter Wing, Mio Sakamoto, takes note of. Yoshika initially turns down Mio Sakamoto's offer to join the Witches, but after receiving a letter from her supposedly dead father suggesting he worked with Mio in the past, Yoshika decides to join her on the voyage back to the 501st base. Once they arrive, Mio reveals to Yoshika that her father was the one who created the Striker Units the Witches use to fight the Neuroi. He strongly believed this science could save the world, and wanted Yoshika to use her powers to protect people. Though Yoshika is anti-war, she decides to join the 501st to honor not only her father's wishes but her own desires to protect those she loves as well.
Following this introduction, many subsequent episodes spend time acquainting Yoshika with the other members of the 501st Wing. At first, the soldiers are harsh towards Yoshika, hazing her and doubting her abilities to fight the Neuroi on the frontlines. But with time, Yoshika proves herself and the other pilots start treating her as part of the family.
An important fact about the Witches is that, as they age, they start losing magical powers until eventually, they're unable to use magic and pilot the Striker Units. During a battle, Minna noticed Mio's shield wasn't fully protecting herself anymore and orders her to stop fighting. Mio brazenly ignores these warnings, and as a consequence, gets seriously injured when trying to prevent Yoshika from interacting with a mysterious human-like Neuroi. It is later revealed this Neuroi was warning Yoshika that scientists in the military were taking a Neuroi core to power their mecha. That mecha loses control, causing the Witches to get together, destroy the Neuroi nest, and free Gallia, allowing the team to finally return to their homes.
Strike Witches Season 2
Six months later at her home in Fuso, Yoshika receives yet another letter from her deceased father, this time detailing a special Striker Unit he created. Yoshika delivers this info to Mio, however, both soon discover a new Neuroi nest has appeared, this time over Venezia. With this news on the airwaves, Minna reunites the 501st Joint Fighter Wing to combat the Neuroi.
While Yoshika uses the Striker Unit her father made to hold her ever-growing magical power, Mio trains to learn the True Reppuzan, a skill only Fuso Witches can learn. The technique drains Mio's powers, but with her magic slowly dissipating anyways, she needs tricks like this up her sleeve to be useful in battle. To destroy the Neuroi nest, the military comes up with another harebrained scheme to use Neuroi technology to power up their battleship. This, of course, goes terribly as the Yamato loses control of its ability to repair itself. Mio, refusing to lose, uses the last of her magical ability to power the ships' cannon and destroy the Neuroi nest. Unfortunately, this plan fails as it is revealed the Neuroi were using a shield to protect its core, and it thus absorbs Mio into its body. All hope appears lost, until Yoshika, with the help of the rest of the troop, retrieves Sakamoto's fallen sword and accomplishes the True Reppuzan. With this, Yoshika saves Mio and destroys the Neuroi, but at a major cost: she loses her magic in the process.
Strike Witches: the Movie
With the Neuroi nest over Venezia obliterated, the Witches yet again go their separate ways. Since Yoshika lost her magical powers, she begins her medical career in Fuso. Life appears rather peaceful until Yoshika encounters a new Fuso Witch.
Enter Shizuka Hattori, who hands her a visa to study at a medical school in Helvetia. At first, Shizuka was ecstatic to meet her war hero idol until she discovered Yoshika isn't quite how she imagined her to be. While traveling to the medical school, their ship collides with an iceberg, causing crew members to be trapped in a room on fire. Ignoring orders to leave them behind, Yoshika crawls through a space to turn on the sprinklers and rescue the workers. To Shizuka, this was brash and dangerous, but to Yoshika, it was necessary to save their lives no matter what. As the two travel together and encounter Neuroi, Shizuka's distaste towards Yoshika's heroism turns to respect as she admires the degree to which Yoshika goes to save lives.
Shizuka attempts to fight off the new Neuroi on her own, but is shot-down and knocked unconscious. Despite having no magical abilities, Yoshika works to drive the Neuroi away from the village shelter. In the midst of battle, Yoshika is seriously injured and Hattori wakes up, feeling guilty she was unable to protect Yoshika. Over an intercom, the rest of the 501st hear Hattori's pleas and rush over to join the fight. As Yoshika lies on the ground, she hears the voices of her team, and perhaps through the power of love and friendship, regains her magical abilities and heals her wounds. As the 501st fight the Neuroi, Sakamoto comes in via plane to drop Yoshika her Striker Unit, allowing her to rejoin the battle, defeat the Neuroi, and ultimately, reform the 501st Joint Fighter Wing with Shizuka Hattori in tow.
Other than the Strike Witches, there are other Witches that exist in the World Witches franchise. Brave Witches follows the 502nd Joint Fighter Wing and the soon-to-be-released Luminous Witches is about a musical squadron. If you want even more Strike Witches fare, there's also the OVA series Operation Victory Arrow, the manga The Sky that Connects Us and the short series 501st JOINT FIGHTER WING Take Off!