Running at a mere 21 minutes, the 2021 documentary "Under the Helmet: The Legacy of Boba Fett", that I only assume came into being because of the upcoming "The Book of Boba Fett" TV series, was good enough for a single viewing.
Personally, then I found that "Under the Helmet: The Legacy of Boba Fett" offered nothing new to me. This was all stuff that I had seen or heard before. But it was still watchable and enjoyable for what it was. And I suppose for the casual "Star Wars" viewer or new-coming fan, then director Brian Kwan's 2021 documentary offers some great insight into the phenomena that is Boba Fett.
Sure, "Under the Helmet: The Legacy of Boba Fett" was a little bit of enjoyable documentary, but it wasn't something that made me go 'wow'. Nor is it something with enough contents to it to support more than just a first and single viewing.
My rating of "Under the Helmet: The Legacy of Boba Fett" lands on a bland five out of ten stars.