Free!-Eternal Summer- Rediscovery Book

Free!-Eternal Summer- Rediscovery Book (TVアニメーション Free!-Eternal Summer- Free!-Eternal Summer- Rediscovery Book TV Animēshon Free!-Eternal Summer- Free!-Eternal Summer- Rediscovery Book) is a fan book of the Free!-Eternal Summer- series.

Summary
The fan book features full-color storyboards of major scenes from Eternal Summer alongside extensive commentary from the staff. Also featured is a special collection of the characters in alternative outfits, such as those worn in the FUTURE FISH ending, along with character profiles. The book is split into different sections, each focusing on different elements (character profiles, staff interviews, scene details, etc.) with section titles including "Character Fashion Collection" and "Impressive Scenes with Artist Commentary".

The book is a sequel to the fan book of the same name for the first season, Free! Rediscovery Book. The content of the Eternal Summer book is identical in terms of layout to this first book; but, as the different names suggests, the first book covered scenes and content from the original series while the sequel focuses exclusively on the second season.