Hawaii Five-0's Danno is barely keeping his temper in check in two new sneak peeks for "Ka Makuakān (Family Man)."

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When the daughter of a Navy Seal goes missing, McGarrett (Alex O'Loughlin) and Danno (Scott Caan) will have their backs to the wall. The Navy won't explain exactly what op. the youngster's father is on - that's classified, after all - and Five-0 won't revive any support with their theory that the two events are related (see first video below).

A missing child case always strikes close to home for Detective Williams, and finding out his younger brother is in a similar predicament will not abate his annoyance. Instead, Danno will be ready to throttle Marco Reyes (Anthony Ruivivar), cocky personality and all, when he discovers that the baddie has a gun to Matthew Williams' head (see second video below).

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The pressure is on for Danno as he struggles to locate the $18.5 million needed to free his delinquent sibling. Don't think the series will give the hair gel master an easy way out either. The Williams brothers' plight won't be quickly resolved.

Find out more when Hawaii Five-0 airs Fridays at 9 p.m. ET on CBS. Scroll through the photos above to see what's next for Five-0.