Time-Travel is the act of magically travelling from one point of time to another, featured on ABC's Once Upon a Time.
Four ingredients are required to active a time-travel portal allowing one to enter a different time period:
- A resilient heart
- A symbol of innocence (i.e. a baby)
- A symbol of courage
- A brain
- Zelena Mills – the only known person to decipher the laws of time-travel. Although she originally intended to go back in time and change her own past, Zelena opts for murdering Maid Marian and impersonating her so she is brought back to the present. For the ingredients, Zelena uses Regina's heart, Rumplestiltskin's brain, Prince David's broken sword, as well as Snow and David's infant son Neal.
- Emma Swan – accidentally gets sucked into the time-travel portal to the Enchanted Forest of the past.
- Killian Jones – follows Emma into the portal in an attempt to save her.
- The ingredients required for time-travel (heart, brain, courage and a child) are based on the elements requested of the Wizard of Oz in the story The Wonderful Wizard of Oz.
- S3, E20: "Kansas"
- S3, E21: "Snow Drifts"
- S3, E22: "There's No Place Like Home"
- S4, E17: "Heart Of Gold" (flashback)