Unable to understand her daughter's feelings for the anesthesiologist, the relationship between Noriko (Okazaki Sae) and her mother Seiko (Ikezu Shoko) deteriorated. She ran away from home, and Kazuhiro (Sugino Haruka), Rei (Miyazawa Emma) and Shingo(Kouji Mukai) Drinking in the shop.At this time, Shingo's son Keigo (Yuda Yuki) suddenly visited, and his mother Rin (Tomite Mami) objected to his participation in scheduled mountain climbing activities as a schoolchild.In fact, Keigo has a heart disease. Considering his physical condition, Rin's objection is natural, but Keigo also wants to climb mountains like his friends and catch his favorite giant beetles.Since he was the son of his childhood sweetheart, Bu wanted to fulfill his wish and suggested that he go to MMT's mountain clinic for treatment.

Keigo's doctor is Jiang Sen (Omori Namo), a new member of MMT.The result of the examination was that if a catheter operation was performed, exercise would be possible. Rin was convinced and decided to respect Keigo's wishes and have the operation.Even so, Rin still feels uneasy about climbing, and Ayumu offers to accompany him on the climb.

The operation was successfully completed, and Keigo headed to the mountains with Ayumu and Ling.However, on the way, a climber who climbed the mountain with light equipment contacted him and said he was injured. As a doctor, Bu couldn't ignore it. After hesitation, he decided to return immediately and rush to the injured person.However, at that moment, bees appeared on the path where the children were playing, and Keigo was stung by the bees, causing an allergic reaction——.