In over 30 seasons, The Simpsons has introduced all types of characters, and there are two that have had viewers wondering about their relationship for years: Lenny and Carl, Homer’s co-workers and friends. The Simpsons started as a series of animated shorts for The Tracey Ullman Show in 1987, and was developed into a half-hour prime time show three seasons later, making its official debut on Fox in 1989.

Since then, The Simpsons has become the longest-running American sitcom, and has also expanded to other media, most notably comic books and film. The series has introduced the people closest to the Simpsons family, along with other notable citizens of Springfield, who have become part of pop culture and have also built some mystery around them. Such is the case of two of Homer’s closest friends: Lenny and Carl.

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Homer met Lenny and Carl way before they began working at the Springfield Nuclear Power Plant, and along with Barney Gumble, they are his best friends. Lenny and Carl are inseparable, and their relationship has sparked many questions, as they are often portrayed as a couple, but there have been other details hinting at the contrary.

The Simpsons: Lenny & Carl’s Relationship Explained

The Simpsons Lenny Carl park

Leonard “Lenny” Leonard made his first appearance in season 1’s episode “Life on the Fast Lane”, and he’s a Technical Supervisor at the Springfield Nuclear Power Plant. He has a master’s degree in nuclear physics but he’s portrayed as a simple and often naive man. Carlton “Carl” Carlson made his debut in the following episode, “Homer’s Night Out”, and he’s Safety Operations Supervisor at the Power Plant. Very much like Lenny, he has a master’s degree in nuclear physics, and it has been implied that he was a war hero. Lenny and Carl are inseparable, and the series has hinted at an actual romantic relationship between them multiple times.

Lenny and Carl being a couple is a running gag in The Simpsons, and the writers often play with it with double entendre or through visual jokes. Lenny is the one who usually displays his feelings towards Carl, with the latter trying to play it down. Lenny famously carved Carl’s face on a mountain and called it Mount Carlmore, and saw his face in the stars when the residents of Springfield were stargazing to see deep within their hearts and souls (and Carl saw his own face in the stars). Lenny also published a newspaper called The Lenny-Saver with the headline “The Truth About Carl: He’s Great”, of which he was very proud, and a framed photograph of Carl can be seen at his home.

Other occasions that have pointed at a romantic relationship between Lenny and Carl are when Marge’s popsicle sticks sculptures were destroyed and Lenny and Carl’s were mashed together, with Lenny saying that he didn’t know “where Carls ends and I begin!” and Carl quickly replied “it’s statements like that that make people think we’re gay”. One time at the Springfield Baseball Stadium, while watching the Kiss Cam, Lenny reminded Carl when they used to do that... with their respective girlfriends. Though they have been shown holding hands, there have also been references that point at them being straight, such as both having mistresses. Lenny and Carl’s relationship in The Simpsons will be whatever each viewer wants it to be, as the series will surely keep playing with it and won’t confirm if they are a couple or just friends.

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