Danny's nephew is back on Hawaii Five-0, and his lab skills will be key to solving the island's latest murder.

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To refresh your memories, Danno's (Scott Caan) nephew Eric (Andrew Lawrence) first arrived in Hawaii back in season 3. A troubled high school grad with no job perspectives, Eric found that not only was he interested in CSI work, but he also had a knack for sussing out overlooked details. Four years later, Eric has returned to Oahu and is ready to help his uncle break a scuba case wide open.

Unfortunately for Danny, Eric's college education didn't quite smooth out all his rough edges. The lab rat's still an unabashed flirt, but a new sneak peek sees Danno school him in respect (see video below).

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The clip even turned out this gem, which pretty much sums up Eric to a tee:

"Less caffeine, tone down the misogyny. I'm all over it," Eric assures his uncle.

Elsewhere, Steve McGarrett (Alex O'Loughlin) will spend "Ua 'O'Oloku Ke Anu I Na Mauna (The Chilling Storm Is on the Mountains)" preparing to propose to Catherine Rollins (Michelle Borth).

Catch Hawaii Five-0 every Friday at 9 p.m. ET on CBS.