Agent Grant Ward may have the best espionage scores since Natasha Romanov, but can the double agent defeat a seemingly unbeatable lie detector on Agents of SHIELD.

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The turncoat has made it to Providence just in time for Koenig to roll out one of Director Fury's newest toys. It appears the eye-patch donning head of SHIELD wanted a lie detector that even Black Widow couldn't beat (it's unknown if she ever did), and ever member of Agent Coulson's team will have to pass the device in "The Only Light in the Darkness."

Unfortunately for Ward, he has quite a few secrets up his sleeve. Even if the don't come tumbling out during Koenig's inquiry, Dalton promises viewers will find them out soon enough.

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"I think they do a really good job of developing the character so that it's not a switch for pure shock value," Dalton explained to Comic Book Resource. "You do understand why he is the way he is."

While the Marvel actor has been unable to disclose any real details about his past, he did reference his debt to Garrett (Bill Paxton) while speaking with Marvel.com.

"I think Garrett offered him a [purpose]," Dalton said. "He's someone that's always felt [like he was overlooked], and he's somebody who doesn't always know what to say but is eager to speak, [yet] doesn't feel like anybody's listening or anybody cares."

Watch a sneak peek for "The Only Light in the Darkness" below and catch up with Agents of SHIELD when it airs Tuesdays at 8 p.m. ET on ABC.