I first learned this beautiful sword form in 2016. It is unusually dramatic and theatrical, having its origin in a hugely popular song and both television and film dramas, the latter dating back to 1931.
This time around I found the following video on sword flowers (剑花 jiànhuā ) very helpful:
For more about this form, names of the movements, lyrics of the song, and links to instructional and performance videos, see these earlier posts:
Yi Jian Mei is not without its detractors. Some say it is not even Tai Chi Sword, and in fact, it is not. It is 抒怀剑, shūhuái jiàn, lyric (lit. express emotion) sword. The originator of this type of sword, and creator of the popular Yi Jian Mei sword routine, is 朱俊昌 Zhū Jùn Chāng. Read about him and shuhuaijian here: http://www.shuhuaijian.net/ [I owe thanks to Song Chen and Martin Mellish for this information.]
Professor Zhu is a teacher of dance, but he was trained in the martial arts from an early age. Odd as some of the movements in Yi Jian Mei might appear, I have seen most of them in one source or another in less well known, but definitely authentic, Tai Chi sword forms.
For example, this (to me) odd-looking position, called Fukan Renjian in Yi Jian Mei, is from the Michuan (secret) Yang Sword form that Yang Luchan taught the Manchu Imperial guards in the 1850s. The illustration here is from Scott Rodell’s excellent book on Chinese Swordsmanship.
The movements of Yi Jian Mei are so intricate that it’s hard to imagine using them in an actual swordfight, but though intricate, they are composed of familiar jianfa. I have modified my own practice of Yi Jian Mei to stay within bounds of the Tai Chi sword that I am familiar with.