Fringe and Sleepy Hollow alum John Noble is about to arrive in the Arrowverse, where he will portray the main villain on DC's Legends of Tomorrow.

Noble's arrival, announced via EW.com, takes place in the season's fifth episode. However, fans shouldn't expect to actually see the actor, as he's been tapped to provide the voice of Mallus, the big bad behind the Legends' current woes. For the time being, the show plans to keep the villain as a voiceless whisper.

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"That’s the big mythology of the season," executive producer Mac Guggenheim explained. "hat makes Mallus cool at this stage of everyone’s viewing experience is that right now he is just a name and is this whisper."

In fact, Legends' Mallus is actually dead, and while Legends of Tomorrow does have a tendency to resurrect those who have departed the earthly plane (it is a time-travel show, after all), for the moment, at least, there are no plans for Mallus to return to the living. Even if the show should make that move in the future, its no guarantee Legend would actually bring him to physical life. After all, Legends' sister show, The Flash, famously enlisted actor Tony Todd to voice Zoom, who was eventually revealed to be played by Teddy Sears, while Barry Allen's future identity of Savitar was voiced by Tobin Bell rather than Grant Gustin.

Airing Tuesdays on The CW, Legends of Tomorrow stars Victor Garber, Brandon Routh, Caity Lotz, Franz Drameh, Maisie Richardson-Sellers, Tala Ashe, Amy Pemberton, Arthur Darville, Wentworth Miller, Nick Zano and Dominic Purcell.