1.Peter Laird and Kevin Eastman (the co-creators of Teenage Mutant Ninja Turtles) created the comic book characters by chance. They were trying to make each other laugh when Kevin decided to draw a turtle in a mask as a superhero and that end up sparking the idea.
2.Peter and Kevin only agreed to a licensing deal if they had final say on everything.
3.Mark Freedman — who approached Peter and Kevin to represent them in licensing the characters — took a giant foam TMNT turtle they had to help sell the line to toy companies.
4.Every major toy company turned down the Teenage Mutant Ninja Turtles line, 'cause they thought it was a crazy idea and that it wouldn't sell.
5.Mark approached Playmates (who would end up producing the line) as a last resort. Teenage Mutant Ninja Turtles was the first action figure line the company ever created, prior to that they primarily made dolls.
6.When developing the toyline, the creators at Playmates had to flesh out Shredder more 'cause he had actually been killed in the first issue of the Teenage Mutant Ninja Turtles comics.
7.In the original design of the action figures, the Turtles had a tail (like in the comics), but it was removed 'cause it looked too phallic.
8.Mark Taylor — who co-created the He-Man line for Mattel —was brought in to help finalize the designs for the action figures and accessories.
9.The toy line was developed before the cartoon series.
10.Originally the Turtles all had the same colored bandanas.
11.It was during the creation of the Teenage Mutant Ninja Turtles cartoon series that the Turtles were given different color bandanas, belts with their initials on it, and distinct personalities.
12.Chuck Lorre — who is best known creating Two and a Half Men and The Big Bang Theory — wrote the theme song for Teenage Mutant Ninja Turtles (in fact, it's his voice in the spoken parts).
13.The series originally premiered as just a five-part miniseries in December 1987.
14.After the series debut, Toys 'R' Us was the first major retailer to place an order for the toy line, but it was low and the toys sold out almost immediately.
15.The Teenage Mutant Ninja Turtles line would go on to be one of the best-selling toy lines of 1988.
16.And finally, after the movie was made everyone involved with TMNT thought the Teenage Mutant Ninja Turtles cartoon and toy line would be dead because of the film's pretty dark tone.