Mahou Tsukai Tai or "Magic-User's Club" is a 1996 magical Girl/Boy anime. The magic club of Kitanohashi High School is thought by others to be a common parlor trick club, but in reality the members practice actual magic! When an enormous alien cylinder called "The Bell" defeats all the world's military and then just sits there and watches people, the club members think otherwise. Time to defeat the aliens and save the world!
From Wikipedia:
Magic User's Club (魔法使いTai! Mahō Tsukai Tai!?) is a magical girl/boy anime, released as a six-part OVA in 1996 and then a 13-episode TV series in 1999, which was broadcast by WOWOW, and then by the anime television network, Animax, across its respective networks worldwide, including Southeast Asia, South Asia and other regions. The original plan was done by anime director Junichi Sato, with animation produced by Triangle Staff and Bandai Visual. There were also two manga series made, a shōjo manga version by Tammy Ohta (太田 多美 Ōta Tami) and shōnen manga version by Shamneko (紗夢猫). The Magic User's Club anime is released in North America by AnimeWorks.
Plot:
OVA:
An enormous cylindrical alien spaceship, which people call "the Bell" (釣り鐘 Tsurigane), descends upon Earth one day. Multinational military forces attack it, but the Bell's defenses easily vaporize all human weaponry. The story takes place one year afterwards. The Bell, which seems to have no living crew, has sent out robotic probes to explore and analyze human civilization. It soon became apparent that the Bell's defenses and its probes only destroy whatever attacks them first. As such, most people have adapted to the Bell's presence on Earth and are once again going about with their everyday lives, just making sure to stay out of the way of the probes when they pass by. For most of the series, the Bell hovers quietly above the ocean, several miles from Tokyo. A lot of people, however, due to a message sent by the Bell, believe the Bell may eventually attack and conquer Earth, and are working to figure out a way to stop it.
TV Series:
The Bell has been defeated, its "crew" having retreated into space, but a massive cherry tree stands in its place above the city. The Magic Club must meet once again to solve the problem of the giant tree, which is blocking off sunlight for the city. A mysterious figure descends from the tree and watches over the members of the club as they continue to deal with magic in their daily lives.
