The setup
Cassilda's Song (2026)
The same weekend also brings Hope. Two trailers, one argument about which one wins the window.
Cassilda's Song opens in theaters on September 12, 2026.
Reactr / Trailer Reactions / Cassilda's Song
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In Theaters · September 12, 2026
Cassilda's Song
Trailer Reactions
Horror · Drama
Have you found the Yellow Sign?
Based on The King in Yellow by Robert W. Chambers, Cassilda's Song follows Cassie, a gifted but insecure art student who becomes obsessed with Sylvia, an enigmatic model whose presence seems to awaken something extraordinary in her work. What begins as creative admiration becomes intimacy, ritual, and obsession. As Cassie's art grows increasingly strange and symbolic, her desire to create something perfect begins to consume her.
Free · no editing · camera or voice only · the clip is yours to post
The Trailer
First look: the Cassilda's Song trailer
Dropped August 10, 2026
Production notes
The history behind Cassilda's Song
Direction comes from Jordan Ros. It clocks in at 2 hours 30 minutes.
Who’s in it
Who you’ll see in the trailer
On screen, it is Setaria DePue, Katie J. Kell and Nathon Cash carrying the story. Setaria DePue plays Cassilda "Cassie".
The reason to record this one
This trailer was made to be reacted to
The best horror trailers do not explain, they unsettle. Record the moment your stomach drops before your brain catches up.
By opening weekend everyone will have a take. The reactions that matter are the ones recorded before the takes calcify.
Reactions on Reactr
Be one of the first to react
Reaction clips for Cassilda's Song will appear here as Reactors share them. The Reactr recorder is free for creators: watch the trailer, record on camera or voice only, and the finished clip is yours to post on your own TikTok, Reels, or Shorts channel.
Record the first reaction →FAQ
Cassilda's Song: quick answers
How do I record a Cassilda's Song trailer reaction?
Open the reaction recorder on your phone at reactr.film/studio/cassilda-s-song, choose camera or voice only, and press record while the trailer plays. Reactr captures your reaction and gives you a share-ready clip when the trailer ends. It is free.
Do I have to be on camera?
No. Voice Reaction mode records your commentary with the microphone only: the camera stays off, no face is recorded, and you still get a share-ready clip for your channel.
When does Cassilda's Song come out?
Cassilda's Song is scheduled to open in US theaters on September 12, 2026. Dates can shift, so check back for updates.
Who stars in Cassilda's Song?
Setaria DePue, Katie J. Kell, Nathon Cash, Drew Crosby and Raquel Amezcua lead the cast, directed by Jordan Ros.
Is Reactr free?
Yes. Recording reaction clips on Reactr is free, with no paywall on the finished clip. You own your clip and can post it to TikTok, Reels, Shorts, or anywhere else. Reactr makes money from studios and sponsors, not from creators.
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Your first reaction only happens once
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