Leathertello

Leathertello is the slash ship between Leatherhead and Donatello from the Teenage Mutant Ninja Turtles fandom.

Touch and Go
Donnie and Leatherhead are setting up the entertainment system, when Mikey comes over and jokingly places a tinfoil hat on his head. Donnie asks what he's doing and Mikey says he wants some TV. Donnie scolds him, since he and Leatherhead are in the middle of a very delicate procedure. Mikey eventually makes Leatherhead very angry, but Donnie calms him down. He tells him not to listed to Mikey, since he annoys everyone.

Hunted
Leo leads the boys and Leatherhead back home, but Leatherhead says that he can't return with them due to his uncontrollable anger. Donnie says that they can help him learn to control it, but Leatherhead doesn't want to risk it. Donnie then thinks that he may have a solution, and leads them to another part of the sewers. He has Leatherhead open some steal bars and leads them to an old subway station. He says that it'd be great for Leatherhead, and is still only three minutes away from them. Leatherhead doesn't know how to thank them, but Mikey says that he doesn't have to since they're family.

Exodus
Donnie and Leatherhead are on the same team to enter the Shredder's tower, entering into a tunnel. Donnie remarks on how large it is, and Leatherhead says it's been recently constructed. He says that at least the coast is clear, when the two are suddenly attacked by invisible ninja's. Leatherhead easily takes them out, and Donnie comments that he's glad he brought him along. They then get below the Shredder's mansion, and discover that he's been creating a rocket.

Adventures in Turtles Sitting
The boys take a DNA sampling of a very mutated Donnie to Leatherhead, who studies it. He finds that Donnie was affected by the Outbreak Mutagen. Leatherhead regrettably has no way of curing him, but the boys are still going to need to capture him. Leatherhead says that he and Donnie had created a containment unit to capture larger mutations, and sadly remarks that he never imagined they would have to use it on Donnie.

Good Genes
Leatherhead remarks to Leo that he also wants to talk with Donnie, given that he had worked on most of the cure for the outbreak mutation. He fears that his progress is too slow without him, and that it's only a matter of time before Donnie is lost for good. Leo says that they may have to go to Bishop, when Donnie attacks Mikey. Leatherhead releases a gas to calm him down, but Donnie becomes resistant to it. Leatherhead decides that he'll need to work on stronger tranquilizers, while Leo decides that it's time to go to Bishop. Leatherhead knows where he is, but it's a long journey and Donnie might not make it.

Just as Bishop is about to shoot Donnie, Leatherhead grabs him and knocks him aside. He says that Bishop will not touch Donnie, and that if Donnie has to be subdued, he will do it. Donnie then attacks and Leatherhead is forced to fight him. They end up in Stockman's lab, which causes Leatherhead to have a traumatic flashback to his time there. Donnie is about to attack, but Leo is able to stop him before he can hurt Leatherhead.

When the turtles go off to steal the artifact for Bishop, Leatherhead says that they need to administer the cure to Donnie soon. He asks Stockman where the cure is, who reveals that there is none. Leatherhead is about to destroy Stockman, but Splinter says that this won't help Donnie. Bishop then enters and Leatherhead is about to attack him, but Bishop says that if he does so, Stockman won't work on a cure and they loose all chance of saving Donnie. Leatherhead relents, and starts working on the cure with Stockman.

What a Croc!

 * Donnie watches Mikey's video feed of Leatherhead.
 * Donnie asks if Leo and Raph think it was a bad idea to get Leatherhead mad, and they both agree.
 * Donnie is amazed that Leatherhead is building a transmatt.

Touch and Go

 * Leatherhead and Donnie work on the last bit of the entertainment system.

Hunted

 * Donnie asks if Leatherhead can help him with an invention.
 * Donnie asks if the others think Leatherhead overreacted.
 * Donnie assures Leatherhead that everything is going to be fine.
 * Donnie stops the fan so that he and his brothers can save Leatherhead.
 * Donnie can't believe Leatherhead gave his life for theirs, but Leatherhead is revealed to be alive and corrects him.

Bishop's Gambit

 * Leatherhead points out a signal to Donnie.

Exodus, Part 1

 * Leatherhead and Donnie plug Honeycutt into the computer.

Adventures in Turtles Sitting

 * Leatherhead knocks Donnie into the containment unit.
 * Leatherhead sympathizes with Donnie being a monster.

Good Genes, Part 1

 * The episode intro had Leatherhead remarking on how kind and intelligent Donnie is.
 * Leo calms Leatherhead down when he sees Bishop, by telling him to remember that they're there for Donnie.
 * Donnie throws a part of the containment unit at Leatherhead.
 * Leatherhead tells Leo that they can't leave Donnie to Bishop and Stockman.

Good Genes, Part 2

 * Leatherhead catches Donnie when he nearly passes out.

Fanon
Leathertello is a pretty common ship among TMNT fans. The ship is popular among TMNT 2003 fans. This is due to the two both being scientists and often bonding over their shared love of it. However the ship has less fans in other TMNT media, specifically in the 2012 fandom. Specifically due to Donnie and Leatherhead rarely having many positive interactions. As well as the 2012 series not adapting Leatherhead to be a scientist, taking away their main commonality in the 2003 series.

On AO3, Leathertello is the second most written ship for Leatherhead and the fifteenth most written for Donnie. There are currently 49 written works.

Fandom

 * FAN FICTION


 * TUMBLR

Trivia

 * In the season 4 and 5 intro, Leatherhead is in Donnie's section.