In 2018, Mantock landed the anchor role of Macy Vaughn in The CW's reboot of Charmed. As the eldest sister and a practical molecular geneticist discovering telekinetic powers, Mantock brought psychological depth to an otherwise lighthearted fantasy property. Her performance carried the show through its first three seasons, garnering critical praise even when the writing drew divided reactions from fans of the 1998 original.
In July 2021, Mantock announced her departure at the conclusion of Season 3. The decision caught many viewers off guard, yet it reflected a desire to explore new creative directions rather than remain tied to long-term television contracts in Vancouver. In her formal exit statement, Mantock expressed immense gratitude to the cast and crew, emphasizing that playing Macy was a privilege while indicating a clear readiness for fresh challenges.
She did not remain idle. Mantock returned to the United Kingdom, quickly making her West End debut in Harold Pinter's production of Anton Chekhov's The Seagull alongside Emilia Clarke. Soon after, she joined the prestigious Royal Shakespeare Company, tackling major classical roles in Stratford-upon-Avon. This transition back to live performance reinforced her identity as a technically trained stage actor who chooses creative growth over Hollywood commercial convenience.
