Set in and around the corridors of power, Bodyguard tells the fictional story of David Budd (Richard Madden), a heroic but volatile war veteran now working as a Specialist Protection Officer for the Royalty and Specialist Protection Branch (RaSP), assigned to protect the ambitious and powerful Home Secretary Julia Montague (Keeley Hawes).
However viewers were left stunned in Sunday night's show when Keeley's character Julia died of injuries sustained in a bomb blast from the previous week.
Now Bodyguard creator Jed Mercurio - who is also behind hit BBC series Line Of Duty - has spoken out about the decision to kill off a main character.
He told the Radio Times this week: "I think there’s a certain expectation with series TV that it will always orbit around an equilibrium, in which nothing much changes for the main stars, and there are no drastic changes to the set-up, especially now things tend to run for several series.
"But, with my work, I like to try to do things that move the story on, and with Bodyguard I wanted to have this event mid-series that would completely alter the dynamic."
Mercurio added: "I remember watching TV as a kid and, whenever there was some sort of jeopardy involving the hero, I could reassure myself that they were what I’d call a 'can’t-die' character, so everything would be OK."
Following the weekend's show, Kelley spoke out on Twitter: "It has been amazing to be part of #Bodyguard. Everyone’s enthusiasm for the show has made it so exciting.
"Thanks again for watching and for the lovely messages. And Iiiiieeiiiieeeiiiiiiiiii will always love youuuuuuuuuuuuu! @_richardmadden (sic)."
Despite Mercurio's comments, some fans are convinced that Julia may still be alive.
Bodyguard continues Sunday nights at 9PM on BBC One. A special extended finale episode will run for 75 minutes later this month.