(written from a Production point of view)
Alan Marcus (died 9 January 2015) was a stuntman and actor who portrayed Yeoman Samno in Star Trek VI: The Undiscovered Country in 1991. Marcus filmed his scenes along with fellow stunt actor B.J. Davis as Yeoman Burke under stunt coordination of Don Pike on Thursday, 2 May 1991, Tuesday, 7 May 1991, Wednesday, 8 May 1991, Friday, 10 May 1991, Monday, 13 May 1991, Wednesday, 15 May 1991, and Friday, 17 May 1991 on Paramount Stage 8, 9, and 12. He also filmed scenes on second unit on Friday, 3 May 1991, along with Davis and Scott Leva on Paramount Stage 13. The first scene Marcus filmed, always listed as "Hitman #2" on the call sheets, was the corridor scene in which his character was found dead.
Marcus started to work in film and television productions in the early 1980s with appearances and stunt work in the action film The Octagon (1980, with stunts by Ken Lesco and Don Pike), the crime drama Defiance (1980, with David Cadiente and stunt coordination by Buddy Joe Hooker), the action film An Eye for an Eye (1981, with Rosalind Chao and stunts by Tony Cecere, Joe Farago, and Mark Riccardi), the crime drama I, the Jury (1982, with Paul Sorvino and Judson Scott and stunts by Phil Chong), the action film Forced Vengeance (1982, with Michael Cavanaugh, David Opatoshu, and Bob Minor), the action film Kill Squad (1982), and in episodes of CHiPs (1982, starring Robert Pine, Lou Wagner, and Michael Dorn) and Tales of the Gold Monkey (1983, starring Stephen Collins and Marta DuBois and with Branscombe Richmond).
Marcus worked as stunt coordinator on episodes of the television series Maximum Security (1984), Dangerous Women (1991, starring Valerie Wildman), and The Secret World of Alex Mack (1994, with John Marzilli), on the action drama The Patriot (1986, with stunts by Kane Hodder, Bud Davis, Gary Pike, Charlie Skeen, and Bobby Burns), the drama Born to Race (1988, with stunts by Eddie Braun, Greg Gault, Eddie Hice, Kane Hodder, and Monte Rex Perlin), and the independent film Hollywood Chaos (1989, stunts by Ed Anders).
Further stunt work includes the action film Lone Wolf McQuade (1983, with Robert Beltran and stunts by Simone Boisseree, Al Jones, and Gary Wayton), the crime thriller Deadly Force (1983, stunt coordination by B.J. Davis), the science fiction film City Limits (1984, with Kim Cattrall, Tony Plana, Kane Hodder, Brian J. Williams, and Gene LeBell), the daily soap Santa Barbara (1985, with Louise Sorel), Nicholas Meyer's comedy Volunteers (1985), the action thriller Invasion U.S.A. (1985, with Richard Lynch, Stephen Markle, Nick Ramus, Maria Doest, and stunts by B.J. Davis, Al Jones, Eric Norris, Don Ruffin, and Lincoln Simonds), the mystery thriller Nomads (1986), the action thriller Avenging Force (1986), the fantasy comedy Hunk (1987, with Hilary Shepard), the action sequel American Ninja 2: The Confrontation (1987), the horror comedy House II: The Second Story (1987), the horror film The Hidden (1987, with Michael Nouri), the comedy The Night Before (1988), the action thriller Rambo III (1988), and the horror sequel Friday the 13th Part VII: The New Blood (1988, with Kane Hodder, Craig Thomas, and stunts by Maria Kelly) for which he auditioned together with Kane Hodder.  About his work with Marcus, Hodder remembered:
- Also present was stuntman Alan Marcus, Hodder's friend and co-worker, who was at least partly responsible for some of the livelier moments on the Part VII set. "Alan doubled for Kevin Blair and another actor, and then at the end of the show, he’s the last one I kill. He did a number of good stunts," praises Hodder. "I was doing one stunt with Alan in which he's on the end of the pier. I have to grab him and throw him backwards off the end of the pier, and he has to land in a rowboat. The cameras were in the rowboat and in the boat next to it. The way things were positioned, everyone was concerned that he wouldn't go far enough to make it into the boat. So I told him to really make sure he went far enough. When we did it the first time, he went so far that he landed between the two cameras in the boat, and they missed the shot. It could've been bad, but it turned out pretty funny". 
Marcus also worked as stuntman on the science fiction/horror film Deep Star Six (1989, with Miguel Ferrer, Matt McCoy, and stunts by Eugene Collier, Maria Kelly, and Kane Hodder), the science fiction film Peacemaker (1990, with stunts by Gary Baxley, Chuck Borden, Jeff Bornstein, George Colucci, Chris Doyle, Dennis Madalone, and Patricia Tallman), the comedy 9 1/2 Ninjas! (1991), the action film Killing Streets (1991), the horror sequel Alligator II: The Mutation (1991), the horror comedy Ghoulies III: Ghoulies Go to College (1991), the horror sequel House IV (1992, with Scott Burkholder, Ned Romero, Annie O'Donnell, Steve Vinovich, and Kane Hodder), the science fiction comedy Mom and Dad Save the World (1992, starring Terri Garr), the horror film The Hidden II (1993, with Raphael Sbarge), the television series Final Appeal: From the Files of Unsolved Mysteries (1992), the thriller No Place to Hide (1992, with Dey Young, Maria Kelly, and Kane Hodder), the horror sequel Jason Goes to Hell: The Final Friday (1993, with Kane Hodder), the horror film Pumpkinhead II: Blood Wings (1993), the comedy Four Rooms (1995), and more recently the crime drama Across the Line: The Exodus of Charlie Wright (2010, with Corbin Bernsen, B.J. Davis, Marty Murray, and Spice Williams-Crosby).
In 2014, Marcus announced that he would work as writer and producer on Esai Morales' family movie Precious Cargo, as stunt coordinator on the crime comedy Bristled, and on the horror film Room and Board. All three films were still in pre-production as of January 2015, but Marcus' involvement won't be possible. According to his close friend and fellow stunt actor Kane Hodder, Marcus passed away in the night of Friday to Saturday, on 9 January 2015.