After regaining her squid-like powers, Ika Musume aims to carry out her mission of eradicating humanity. However, her laid-back stint as a waitress at Lemon beach house leaves her lounging around between tasks. Alongside her pursuit are challenges like evading alien aficionados and attracting the attention of an eccentric girl. Set post the initial season, Shinryaku!? Ika Musume delves into the comical escapades of Ika Musume as she schemes for her upcoming surface world conquest.