Photos by Ben Deibert

The hellacious heroes in a half shell are back! The Teenage Mutant Ninja Turtles celebrated their 25th anniversary Thursday night at the World Financial Center Plaza, where fans proved there was no shame partyin’ it up in full turtle attire (the greener, the better). Part of the Tribeca Film Festival Drive-In movie feature, the Shell-ebration kicked off with free pizza, martial arts demos, face-painting and tours of the memorabilia-packed TMNT party bus, and finished with a free outdoor screening of the original (and arguably best) live-action film, Teenage Mutant Ninja Turtles (1990). Even the Empire State Building glowed green in their honor.

The fearsome fighting team and their gal pal, April O’Neill, were on hand for photo-ops, and to demonstrate some kick-ass moves with help from the American Taekwondo Association. Singing the “Turtle Power” theme song, arguing over which turtle is most likely to score with April, and comparing fake weapons, both the old and new generation of TMNT followers showed serious love for their turtillian brethren. Luckily, this is only the beginning of the turtle comeback: A new film, to be released in 2011, was just announced yesterday. If that doesn’t call for a cowabunga, we don’t know what does.—Elizabeth Pauker