‘Doctor Who’: Watch Jodie Whittaker’s Debut as 13th Time Lord (Video)

The 13th Time Lord was finally introduced at the end of the “Doctor Who” Christmas special

(Spoiler alert: Do not read ahead unless you’ve seen the 2017 “Doctor Who” Christmas special, “Twice Upon a Time.”)

Hello Jodie Whittaker! At the end of the “Doctor Who” Christmas special, “Twice Upon a Time” on Dec. 25, Whittaker became the 13th Time Lord, fulfilling the destiny that had laid before her since her casting as the next Doctor was announced in July.

On Monday night, fans were introduced to Whittaker as the new Doctor, when Peter Capaldi (the actor who has filled the role of the 12th Time Lord since 2013) regenerated into the very first female lead in the show’s 50-plus year run.

In case you were wondering what “regeneration” is, it’s quite simple actually. You see, the Doctor is an alien — a Time Lord, specifically — who can “regenerate” into a new body when he dies. This nifty trick has allowed the show to periodically replace its lead actor and explains how the beloved British series has been able to continue for decades.

The “Broadchurch” star will fully begin her reign as the Doctor next year in Season 11, alongside co-stars Bradley Walsh, Mandip Gill and Tosin Cole.

Watch Capaldi and Whittaker share the limelight in the special’s regeneration scene in the video above.