About

The Marceline Red Flannel Mandela Effect refers to a Mandela Effect phenomenon about the Adventure Time character Marceline the Vampire Queen wearing a red flannel around her waist at some point in the show. Others thought that she wore a flannel open with a tank top underneath. The fan theory spread en masse on TikTok and Reddit in March 2025. Some attested that Marceline did wear a red flannel in the Adventure Time comic book series Marceline and the Scream Queens. However, Marceline did not wear a flannel in the Cartoon Network cartoon. Others noted that Marceline's gender swapped male counterpart Marshall Lee from the Fionna and Cake universe did in fact wear a red flannel. It was guessed that some people conflated the outfits of the two characters.

Origin

On March 25th, 2025, TikToker^[1] @shanna..bannanahh posted a video using the Frank Heffley Schizophrenia sound I Knew That Door Had a Lock on It to comment on "What it feels like to tell people Marceline wore a flannel (they're about to drag me back to the looney cell)." The video received over 758,200 likes in three days (shown below).

The abovementioned video made the Mandela Effect well-known, but it was originally discussed in the /r/adventuretime by Redditor^[2] TransitionDue6954 on January 7th, 2022. They wrote, "Has anyone ever noticed that Marceline never actually wore a red flannel shirt?" The post brought up Marceline's gender swapped character Marshall Lee (shown below), but the Redditor's girlfriend (who apparently hadn't seen much of the cartoon) didn't know who Lee was. The post received 36 upvotes in three years.

Throughout the 2010s and early 2020s, Marceline cosplayers often wore a red flannel, evident in a photo shared by Redditor^[3] to /r/adventuretime on December 9th, 2019 (shown below).

Similarly, on September 20th, 2024, TikToker^[4] @iceiiys posted a video of her Marceline cosplay, which also included a red flannel worn open with a black tank top underneath, receiving over 80,400 likes in six months (shown below).

In the comment section of TikToker^[1] @shanna..bannanahh's March 2025 video about the Mandela Effect, users noted that Marceline wore a flannel in the 2013 Adventure Time comic series Marceline and the Scream Queens. On the first page, sourced from the Internet Archive,^[5] Marceline is seen wearing a red flannel (shown below). However, she never wore the flannel in the TV show.

Spread

On March 26th, 2025, TikToker^[6] @athellos added to the discourse, sharing a video about the flannel being tied around her waist and remembering "the physics of that flannel when she was flying." The video received over 674,000 likes in two days (shown below).

On March 27th, TikToker^[7] @hannahrussell0 shared a similar video, saying in it that she also remembered Marceline's flannel from the TV series. In a day, it received over 16,800 likes (shown below).

Search Interest

External References