Hawaii Five-0's Detective Williams is now the proud father of two, but this double dose of fatherhood will have him wondering which way is up this Halloween.

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His son is deathly ill and his daughter's becoming a teen - it's two of Danno's (Scott Caan) worst nightmares rolled into one. Between Charlie and Grace (Teilor Grubbs), the cop will find both sweet and sour in his candy bag this October.

"The Halloween episode...will be both a treat and trick for Danny, who spends the start of it collecting candy at the hospital with son Charlie, only to then dash to the North Shore to pull Grace out of a wild party!" TV Line teased.

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A still pulled from that episode shows a guilty looking Grace riding shotgun in her father's Camaro:

 Danny & Grace #H50 606

A photo posted by plenkov (@plenkov) on Aug 28, 2015 at 4:21pm PDT

Despite being stuck in the hospital, Charlie will have a far happier Halloween than his big sis. "As grumpy as he is, with kids you see a whole different side of Danny," showrunner Peter Lenkov told TV Line. Catch up with Danny, McGarrett and the rest of Five-0 when Hawaii Five-0 returns to CBS on Sept. 25 at 9 p.m. ET.