Summer Begins.

Summer Begins. (夏、はじまる.) is the tenth episode of the ''Love Live! Nijigasaki High School Idol Club'' anime series. It was aired on December 5, 2020.

Summary
With the first school term now over, the School Idol Club prepares for a summer training camp at the school. They spend most of the first day cooking dinner, and Kasumi Nakasu enlists both Shizuku Osaka and Rina Tennoji, her classmates so they can try to scare the other girls, only for it to backfire on them. Yu Takasaki talks with Setsuna Yuki in the music room about having trouble finding something she loves to do, and on the way back, Ayumu Uehara sees them together. The next day, Ai Miyashita suggests they play tag to break up the monotony of simply jogging, followed by them playing in the pool. Yu tells Ayumu that she will be more courageous and do everything she can for all of the club members. Yu talks to the club members about wanting to organize a school idol festival for various school idol groups. They all happily agreed to what she had said them.

Cast

 * Hinaki Yano as Yu Takasaki
 * Aguri Onishi as Ayumu Uehara
 * Mayu Sagara as Kasumi Nakasu
 * Kaori Maeda as Shizuku Osaka
 * Miyu Kubota as Karin Asaka
 * Natsumi Murakami as Ai Miyashita
 * Akari Kito as Kanata Konoe
 * Tomori Kusunoki as Setsuna Yuki
 * Maria Sashide as Emma Verde
 * Chiemi Tanaka as Rina Tennoji

Trivia

 * International streaming version End Card: Yu Takasaki
 * Setsuna's unusual purple-colored stew is a reference to the "I'm Proud of This Fresh Creation!" illustrated still in Love Live! School Idol Festival ALL STARS.
 * Unlike Ruby, neither Rina nor Yu actually fainted from eating it. (the latter was unaffected thanks to Kanata's meddling.)
 * The friendship conflict between Yu, Setsuna, and Ayumu has been indirectly foreshadowed by this visual, where three of them held hands.
 * The swimwear worn by the Nijigasaki school idols were adapted swimwear designs from Love Live! ALL STARS chapters 18 and 19.

Callbacks to previous Love Live! series

 * This episode shares the series gag of the tenth episode being the summer episode. At the same time this episode makes references to similar events that took place in those episodes:
 * This episode has many narrative similarities with "We've Got Stewshine": both are summer episodes, involves club activities, and starts to develop friendship conflicts between the second year students (in that case, between Yu, Ayumu, and Setsuna).
 * Setsuna leaving Kasumi unconscious with a pillow throw is similar to what Umi did to Nico, Honoka and Eli in the episode "No Upperclassmen Allowed!"
 * Ayumu declaring that she'll stay with Yu forever (with the latter responding that "Granny Ayumu" will look over her) is a reference to You Watanabe and Chika Takami's conversation in Uranohoshi Girls High School.
 * Shizuku's Zombie-like makeup is a nod to her acting as one in the 8th chapter of the Nijiyon Season 3 4komas.

Continuity Notes

 * Ayumu's declaration of staying with Yu forever is a callback to Yu's vow to her in The First Thrill.
 * Yu's proficiency of playing a piano has been improved since Shout Out Your Love.

Errors & Goofs

 * 02:00 Setsuna appears taller.
 * 02:07 Part of walls are unedited; Rina's pockets are missing.
 * 03:21 Missing Karin's moles.
 * 03:32 Ai's legs overlapped the table; an animation error at 03:36 where shadings on Yu's hand is instanteneous upon grabbing the cup.
 * 03:56 Setsuna's hairpin colors are even matched.
 * 04:23 Some details were left unfinished.
 * 12:24 Yu's printed shirt is missing.
 * 12:30-12:42 Ayumu and Yu swapped positions after 3 scenes.
 * 13:36 Markings on the track appears missing.
 * 16:52 Kasumi's upper swimsuit was left unfinished; Setsuna's crossed arms are mismatched to the following scene.

Changes in the BD/DVD release

 * 00:13 Comically drawn eyes were fixed.
 * 02:00 Kasumi and Ayumu's height were adjusted.
 * 02:49 Added splattered soup around the cauldron.
 * 03:32 Foods were given more details and the bottle has been already consumed.
 * 04:28 Recreated panoramic shot.
 * 05:12 Redrawn on Ayumu and Setsuna; removes pathway in the background.
 * 05:24 Alternate animation was given to everyone.
 * 05:30 Added railings on the footbridge.
 * 05:40 Kanata, Shizuku and Kasumi were redrawn.
 * 07:02 Several changes as Ayumu arrives in the room.
 * 07:25 Fixes Setsuna's head as she stands up to follows Ayumu.
 * 08:36-09:30 Altered panning in several shots.
 * 09:42 Minor fixes on Yu's head animation.
 * 10:38 Yu's scene is recreated.
 * 12:13 Third-Years' makeups are looking more terrified; Emma's makeup is noticeably bright.
 * 14:52 A stairway where Karin is heading to was added.
 * 16:35 Nijigasaki members have been redrawn.
 * 16:53 Tattoos were applied on their bodies:
 * Yu's note under her rightmost thigh.
 * Ayumu's heart on her right belly.
 * Kasumi's heart on her right belly.
 * Shizuku drops under her right rear thigh.
 * Karin's ring on her left belly.
 * Ai's hearts were changed to smaller.
 * Kanata's crescent moon on her left belly.
 * Setsuna's stars on her left belly.
 * Emma's orange and star under her left thigh.
 * Rina's icon on her right belly.
 * 17:33 Adds bloom effect.
 * 19:49 Camera panning changed to steady shot.