Danno

Danno was born and raised in Rexburg, Idaho, to Tiffany Paepke, a registered nurse, and Neal Ard, a mail carrier. He attended Madison High School and graduated magna cum laude from Brigham Young University - Idaho with a Bachelor of Science (BS) in Communication. While at Brigham Young University - Idaho, he produced the short film Yarrow's Boy (2013), the feature film The Haunted Swing (2013), and wrote and produced the short film One Door (2014). During this same period, Danno was a camera operator for the BYU - Idaho A/V Services, director at Soapbox Agency, and later promoted to creative director at Soapbox Agency.

MacArthur had agreed to guest-star in an episode of the first season of the reboot, but he died on October 28, 2010, before filming his appearance.

Danny's pistol is an H&K P30 although he carried a SIG Sauer SP2009 in the pilot.

Danny began his career as a police officer with the Newark PD. When he was a patrol officer, he testified against his training officer, Rick Peterson (Peter Greene), under a subpoena during Peterson's trial for corruption. He worked his way up to become a respected homicide detective with 87 convictions before transferring to the Honolulu Police Department. In 2001, he witnessed the murder of his partner Grace Tilwell by a pair of gangsters they had been sent to apprehend. After barely making it out alive, he notices smoke billowing from the World Trade Center and was later ordered to New York City to assist the NYPD. That day still haunts Danny and his daughter Grace was named after Tilwell. He often describes his time with the Newark PD as a "happy time" of his life as he was still happily married to Rachel and Grace was born. Danny is portrayed as a loyal cop who is married to his job first and life second. As a consequence, he is often at odds with his ex-wife Rachel for sometimes not being on time to pick up Grace. He is very loyal to his friends and colleagues, once refusing to believe that his former HPD partner Meka was corrupt even when pitted against overwhelming evidence after the partner was found dead under suspicious circumstances. Likewise, he often gives Steve the benefit of the doubt even when the latter resorts to more "unorthodox" methods in an investigation as he trusts Steve's judgment.

Danny "Danno" Williams is a fictional character from CBS' Hawaii Five-O, and is the partner of Five-0 leader, Steve McGarrett. Williams was portrayed by James MacArthur in the original show from 1968 to 1979, and later by Scott Caan in the series' remake from 2010 to 2020.