How well do you really know your neighbors? That's what the members Hawaii Five-0 will be left asking after several seemingly innocuous people are discovered to be plotting a terrorist attack on American soil.

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During the aptly titled "Pe'epe'e Kānak (Those Among Us)," a radicalized group of students will be at the center of Five-O's next case. Steve McGarrett (Alex O'Loughlin) and his crew will hop on the investigation following the death of a pool cleaner, but few could predict that they would be chasing down everyone from surfers to cops.

A new sneak peek shows that these young bomb-makers will be able to give experienced detectives a run for their money. Unfortunately for them, McGarrett is slowed by nothing, and a little roof jumping will be well within his wheelhouse.

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Then again, everything seems to be within the Navy SEAL's ability range, much to the dismay of Captain Grover (Chi McBride). Fortunately for the SWAT leader, Chin (Daniel Dae Kim) will be giving the Chicago transplant a new way to best his new friend - spear fishing. Check out the second video below to see what a little unhealthy competition will do for Grover's burgeoning fishing skills.

Find out more when Hawaii Five-0 airs Fridays at 9 p.m. ET on CBS.

Tags: television Hawaii Five-O CBS