Teenage Mutant Ninja Turtles (also known as Tales of the Teenage Mutant Ninja Turtles for its fifth season) is an American 3D rendered computer animated television series based on the fictional superhero team. Headed by Ciro Nieli, the series aired on Nickelodeon in the United States from September 28, 2012 to November 12, 2017. It was produced by Nickelodeon Animation Studio and Low Bar Productions. Bardel Entertainment handled layout and CG animation services. The series begins with the turtles emerging from their sewer home for the first time. They use their ninjutsu training to fight enemies in present-day New York City.
The series was first announced in October 2009, following the news that Nickelodeon's parent company Viacom had acquired the rights to the Teenage Mutant Ninja Turtles franchise. The show was created to reach a core audience of boys aged 6 to 11; it was one half of Nickelodeon's strategy to reboot two established brands for new viewers, coinciding with Nickelodeon Animation Studio's development of new Winx Club episodes for girls. In 2011, it was revealed that the show's creative team would be led by designer Ciro Nieli and writers J. R. Ventimilia and Joshua Sternin.
During the months leading to its premiere, Nickelodeon and Playmates Toys released lines of merchandise featuring the new character designs. The two-part premiere took place on September 28, 2012 and September 29, 2012, reaching 3.9 million viewers. The debut ratings were the highest for a Nickelodeon animated series since 2009, leading to a second season pickup in October. Three more seasons followed; the fifth and final season was rebranded as Tales of the Teenage Mutant Ninja Turtles and did not fully air on Nickelodeon, as episodes 115–121 premiered exclusively on its sister channel Nicktoons.
The series was succeeded by Rise of the Teenage Mutant Ninja Turtles in July 2018.