Secrets, secrets are no fun, unless they're shared with everyone. Come on, Agents of SHIELD, you should know that by now.

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Several heads of HYDRA were left writing on the floor following "Aftershocks," but Director Coulson's (Clark Gregg) victory was tainted by a betrayal within his own ranks. Bobbi (Adrianne Palicki) and Mack (Henry Simmons), while not yet donning matching "I <3 HYDRA" T-shirts, closed out the midseason premiere with a little illicit covert bonding sesh.

Poor tiny Lola, the veritable ingénue of the SHIELD family, was unwillingly defiled by Mockingbird's latest plans. The little car may not be able to fly, but Mack certainly tricked it out with some x-ray spy gear, finally using it to located Nick Fury's Toolbox, Coulson's most vital resource.

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Equipped with all of the agency's super double secret documents, the Toolbox contents could prove more than a little deadly if left in the wrong hands. Bobbi and Mack's ultimate plans are unknown, but the duo's trickery could put the nail in SHIELD's proverbial coffin.

"They do have a secret, but whatever they're doing, they think is the right thing," Palicki informed Entertainment Weekly. "It's not necessarily malicious, but you have to keep an open mind."

Well, don't all villains think they are "doing the right thing"? Even if the Bobbi/Mack conspiracy is less catastrophic than originally believed, Simmons warns that their "secret that they have is gonna have quite an impact on the team."

Find out more when Agents of SHIELD airs Tuesdays at 9 p.m. ET on ABC. Click the video below to see a preview for the series' next episode, "Who You Really Are."

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