Calm is introducing a new Sleep Story that is narrated by the voice behind TikTok’s text-to-speech voice, the company announced on Tuesday. Kat Callaghan, a Canadian radio host and voiceover artist who voices the perky and robot-like voice on TikTok, worked with Calm to help users drift off to sleep in a new Sleep Story.

The new Sleep Story, called “Once Upon a TikTok Tale,” takes listeners on an immersive journey where Callaghan describes a series of dreamy locations based on surreal, sleepy versions of popular TikTok trends. The story includes a rhyming script that transitions between certain sections using audio trickery, lo-fi beats vinyl crackles (TikTok-style), ASMR with some L/R panning, and also includes a ~20-minute sleep phase.

Callaghan starts narrating the Sleep Story in her peppy TikTok voice (nicknamed Jessie), then transitions to her normal, far more relaxing voice, getting gradually slower and sleepier as the tale proceeds.

“Recording the Calm Sleep Story was different from anything I have done before,” Callaghan told TechCrunch in an email. “Not only due to having to mix two intonations, but also slowing down the Jessie voice. It is known so well for being fast paced and peppy. While you still get that upbeat tone, you hear it in a whole new way. As different as it might be for those who are familiar with hearing the voice, it was even more strange (in a very cool way) to record the ‘Jessie’ voice in that slower tone. It was certainly a challenge I enjoyed taking on.”

Callaghan says it wasn’t a surprising transition to narrate the Sleep Story after finding out that many TikTok users actually find the text-to-speech narration voice calming, noting that some people even fell asleep to it. She thinks that it’s the sense of familiarity about the voice that comforts people, as it’s a steady and reliable presence, especially for the younger generation.

Given that some people were already falling asleep to Callaghan’s voice, her new collaboration with Calm offers people a way to do so in a more focused sleep setting.