The original animatedTeen Titansseries attracted young and olderfans to Cartoon Networkwhen it began airing in 2003. It ended in 2006, and became a critically acclaimed cartoon show. The spin-off,Teen Titans Go!began airing in 2013. The spin-off has a very different animation style from the original series, featuring a western style that is more cartoonish than anime-inspired.
The question, of course, is: is the new spin-off series connected to theoriginalTeen Titansin any way? Yes, and no. Both series feature the same main superheroes, many of the same villains, and share the same setting. However, the spin-off is more of a standalone series, featuring the same characters but in a different universe. Here’s a more detailed breakdown of thw two.

The Similarities That Connect the Series
BothTeen Titansseries feature the same characters and share the same setting. The heroes are Robin, Starfire, Cyborg, Raven, and Beast Boy. Robin is the leader of the group; he loves planning and perfection, and often keeps to himself. Starfire is bubbly and sweet; she’s an alien that is new to earth, and, as such, is sometimes gullible and doesn’t understand earth culture. Cyborg is half-human, half-robot; he is very interested in technology and often makes inventions for the team and Titan Tower. Raven is quiet and mysterious; like Robin, she prefers to keep to herself. She has an immense power that can completely consume her if she doesn’t keep it under control. Finally, Beast Boy is the entertainer and comic relief of the group; he’s always cracking jokes and is carefree. He has the ability to shape-shift into any animal - although they’re always green.
Besides superheroes, bothTeen TitansandTeen Titans Go!feature many of the same villains, including Gizmo, Blackfire, Mammoth, and Slade. As they are villains, both series feature them committing some crime each episode, and the heroes must stop them. Additionally, both series are set inthe fictional cityof Jump City. The heroes are also based in a T-shaped tower called Titan Tower.

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The Alternate Universe
WhileTeen TitansandTeen Titans Go!seem to be very alike, the similarities stop at the characters and setting.Teen Titans Go!is a standalone spin-off, different in its tone, style, storyline, episode lengths, and the books the characters are in. The originalTeen Titansis darker and more serious, while the spin-off is fun and silly. To ultimately understand what’s happening inTeen Titans Go!, you don’t need to watch the original series.
A crossover movie between both series debuted in 2019, calledTeen Titans Go! vs. Teen Titans. Directed by Jeff Mednikow, the movie is set in the fifth season ofTeen Titans Go!and after the finale of the original series and its film sequel,Teen Titans: Trouble in Tokyo. A character called Master of Games summons the heroes from both series, and pits them against their alternate versions to determine which is best. This movie proves that the series are not connected, in that they are set in different universes.