Though 1985's Cocoon certainly wasn't his first professional gig, that's when the talented actor first dropped onto my radar. The Ron Howard-directed SciFi/Fantasy screened in the summer, and it was clearly a favorite of audiences, much of which was owed to the comic formula of senior citizens discovering a kinda/sorta 'Fountain Of Youth' by way of exposure to alien technology. Dennehy played the otherworldly mastermind who enlists the services of a young boating captain to recover the artifacts, and he also returned for the 1988 follow-up.
To be perfectly honest, the actor gravitated toward much more mainstream fare, and why not? He was a talented heavyweight who could also wear his heart on his sleeve when the role demanded it. He played the authority audiences loved to hate in both First Blood (1982) and Silverado (1985); he played a successful novelist who teams up with a contract killer to help craft his next Best Seller (1987); and the better part of the 1990's and 2000's saw the versatile thespian continuing to explore and create some equally enduring characters in a whole host of projects.
Eventually, the Grim Reaper claims each of us, but -- as I said above -- we'll always have his work in light and shadow to recall the legacy he's left to the arts.