(written from a Production point of view)
Michael "Mike" Papajohn (born 7 November 1964; age 48) is a stuntman and stunt actor who played a Klingon guard on Rura Penthe in the Star Trek: Enterprise episode "Judgment". He received no on-screen credit for his appearance and was identified by the name tag of his costume which was auctioned off on the It's A Wrap! sale and auction on eBay. 
Papajohn was a professional baseball player before he has turned into a stuntman. He is perhaps well known for his role of the carjacker Dennis Carradine, who was involved in the murder of Peter Parker's uncle in the comic adaptation Spider-Man (2002) and the sequel Spider-Man 3 (2007). Kirsten Dunst starred in both films. He played a Cardassian in the 1995 fanatasy film The Indian in the Cupboard, alongside Keii Johnston, J.R. Horsting, Erik Stabenau, Frank Welker, and Christopher Gilman.
He has doubled for stars such as Adam Sander (in The Waterboy 1998) and has also worked as stunt coordinator for films such as A Boy Called Hate (1995).
Papajohn has appeared in several feature films such as Mobsters (1991, starring Christian Slater), The Last Boy Scout (1991), Bound by Honor (1993, with Victor Rivers, Carlos Carrasco, and Tom Towles), Eraser (1996, starring Vanessa Williams), the comic adaptation Spawn (1997, with Melinda Clarke, Faith Minton, and Spice Williams-Crosby), the blockbuster and Academy Award winning Titanic (1997), Paul Verhoeven's Starship Troopers (1997, with Dina Meyer, Brenda Strong, Clancy Brown, and stunts by Mark De Alessandro, Dana Dru Evenson, Anita Hart, and Michael Owen), the academy award winning What Dreams May Come (1998, with Rosalind Chao and stunts by Johnny Martin, Rosine "Ace" Hatem, and Darlene Williams), Charlie's Angels (2000), the action comedy Showtime (2002, with William Shatner), Hulk (2003), the sequel Terminator 3: Rise of the Machines (2003, starring Kristanna Loken), and the sequel Live Free or Die Hard (2007, with Tim Russ, Chris Palermo, Shawn Crowder, and Boni Yanagisawa).
He has also appeared in several television series such as The Practice (1998, episode Line of Duty, with Albert Hall, Cliff DeYoung, and stuntman Alan Oliney), V.I.P. (2000-2001, in multiple episodes), Without a Trace (2004, episode Malone vs. Malone, with Enrique Murciano and coordinated by Dennis Madalone), Threshold (2005-2006, produced by Brannon Braga and starring Brent Spiner), and CSI: Miami (2006, episode Deviant, with Leslie Silva).