Whodunnit?'s Giles the Butler: The Killer Is "Someone I Completely Overlooked"

The contestants on Whodunnit?, ABC's murder-mystery summer reality show, have one objective: to survive long enough to determine who the Killer is, as he/she picks off a new victim each week.But at least one member of the cast has been in a similar situation before.

Giles the butler (Gildart Jackson), is actually employed by the Killer, and guides the players through the game by delivering messages from the Killer and offering them clues along the way.

"Giles is cursed," explains Jackson, who came to TVGuide.com's New York office in character last week. "This isn't the first time that Giles has been stuck in a manor, in a house, where all the guests have been killed. It's happened before."

Meet the contestants of ABC's Whodunnit?

A companion book to the show, Whodunnit?: Murder in Mystery Manor, written by executive producer Anthony Zuiker, reveals the backstory of Giles, including how he was first presented with an offer he couldn't refuse from the Killer. (Read the first five chapters of the book for free here.) The task at hand? Come to the Westlake Estates mansion and act as the puppet master of sorts in the Killer's deadly game. Fast-forward to the TV series, and Giles finds himself in a similar scenario, albeit one at a different mansion and with a different Killer.

"I was lured there, in the same way that all the contestants were," Jackson explains. "I received a package of information along with a very sizable pay package — and, given my circumstances at the time, I couldn't really say no. And alas, it was another one of these serial killers."

Even Giles doesn't know the identity of his employer, however. "I was continually trying to work out who the killer was, just like everybody else was," Jackson says. "I was unable to determine who that individual was until the final episode."

Why reality TV is good for us

Adds Jackson: "It was someone I completely overlooked. ... They were so clever that ultimately, by the time the final episode came down, I was flabbergasted, frankly."

Another thing Jackson found surprising during the course of filming was what the contestants chose to reveal about themselves. (For what it's worth, Jackson's advice to Whodunnit? contestants in possible future seasons is "be honest.")

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"Several people chose not to reveal their true profession. And that was fascinating, when it got revealed what they really did," Jackson says. "There is definitely an aspect of it which is human nature — not only what will they reveal about themselves early on, but also as time goes on what will they share? How will they share their information? With whom will they share their information? Will they lie? Will they tell the truth? And all of that was very revealing, I thought."

In the show's finale, three contestants will be left standing. One dies in the final episode, one is revealed to be the Killer, and the third will be named the winner — and will leave with $250,000.

"It's a guilty pleasure — emphasis on the guilty and hopefully emphasis on the pleasure," Jackson says of the series. "There's this running gag on the show, which is a running gag that has worked very well on American television: Who killed Laura Palmer? Who shot J.R.? Who is the Killer?"

Who do you think the Killer is? Weigh in below!

Whodunnit? airs Sundays at 9/8c on ABC.