(written from a Production point of view)
Outside of Star Trek, McDonough is known for his roles in the 2001 mini-series Band of Brothers and in the television series Desperate Housewives. He is also widely recognized for his performances in such films as Minority Report (2002), Walking Tall (2004), and Flags of Our Fathers (2006).
McDonough was born in Dorchester, Massachusetts, the son of Irish immigrants. He grew up in Cape Cod along with his sister and four brothers. He performed in his first play as a freshman in high school, portraying Snoopy in You're a Good Man, Charlie Brown, for which he received a standing ovation. He graduated from Syracuse University York with a Bachelor of Fine Arts degree in 1988. He then briefly trained at the London Academy of Dramatic Arts and Sciences before embarking on a career in Hollywood.
He made his film debut in the 1990 action thriller Darkman, which also featured fellow Star Trek performers Larry Drake and Aaron Lustig. The following year, he made his first appearance on television, guest-starring in an episode of the war drama series China Beach. Regulars on this series included Robert Picardo, Megan Gallagher, Jeff Kober, and Concetta Tomei, all of whom later performed on Star Trek: Voyager (and, in most cases, other Star Trek series). McDonough again worked with Tomei, as well as Gail Strickland, in the 1992 TV movie The Burden of Proof. He also worked with Kober again in the 1995 film One Tough Bastard.
Early in his career, McDonough worked on several science fiction television projects – each time portraying a drunk with father issues. The first was a 1991 episode of Quantum Leap, the popular series which starred Scott Bakula and Dean Stockwell (later of Star Trek: The Next Generation). This was followed in 1995 by an episode of VR.5 and then by the TV movie White Dwarf. McDonough's co-stars in the latter project included Katy Boyer, Roy Brocksmith, Michael McGrady, Paul Winfield, and Time Winters.
In 1993, McDonough co-starred with Voyager regular Jeri Ryan in the TV movie Ambush in Waco: In the Line of Duty. Gordon Clapp, Richard McGonagle, Glenn Morshower, and Susanna Thompson also appeared in this movie. The following year, he played the supporting role of baseball player Whitt Bass in Walt Disney's hit remake of Angels in the Outfield, in which he co-starred with Star Trek III: The Search for Spock actor Christopher Lloyd. In 1995, he guest-starred on the CBS comedy series Cybill (along with David Clennon and Ken Jenkins) and the NBC drama series JAG (working with Roger Aaron Brown, Spencer Garrett, and Gregg Henry).
In 1996, McDonough had a recurring role on the legal drama series Murder One, working alongside Cecily Adams, Jeff Allin, David Andrews, Jim Beaver, Barbara Bosson, Ron Canada, Michael Ensign, John Fleck, Gregory Itzin, Jack Kehler, Don McManus, Glenn Morshower, Clayton Rohner, Margot Rose, Kenneth Tigar, Titus Welliver, and Rick Worthy. McDonough appeared on several other series in 1996, including Murphy Brown (with John Hostetter) and NYPD Blue (with Gordon Clapp, Sharon Lawrence, Leland Orser, Sierra Pecheur, and Michael Buchman Silver).
McDonough supplied the voice for Dr. Bruce Banner, the Hulk's alter-ego, in the 1996-97 animated series The Incredible Hulk, based on the Marvel Comics superhero. Other voice actors from the series included Matt Frewer, Clancy Brown, Michael Bell, John Rhys-Davies, Kevin Michael Richardson, Jim Cummings and Jennifer Hale. McDonough voiced Banner again for the 2005 video game The Incredible Hulk: Ultimate Destruction, which also featured the voices of Ron Perlman, Daniel Riordan, and Nicholas Guest.
McDonough worked with other Trek veterans in the 1997 TV movies Murder Live! and Invasion. The former project co-starred Caitlin Brown, Terri Garr, and Don Stark; the latter co-starred Star Trek VI: The Undiscovered Country performers Kim Cattrall and Rosana DeSoto. The following year he appeared with Susan Gibney in a two-part episode of Diagnosis Murder and starred in the independent drama Circles with Scott Thomson.
Star Trek: First Contact
A fan of Star Trek, McDonough always wanted to play a role in the series, even if it was only a small one. "I’ve always wanted to be in Star Trek in some way. I’m such a big fan that I would just stand in the background for one of the movies if they asked me." he said. "They had been searching and searching for somebody to play Hawk. I was shooting a movie in Arizona and when I went in to audition for the role I had just arrived back in town and hadn’t slept in almost twenty-four hours. I got in there and I just nailed it." The casting staff were so impressed by McDonough's performance that they offered him the role there and then. 
McDonough was so excited about getting the role that he turned up to the set early before everyone else had arrived. "I got dressed in my Starfleet uniform and walked on the set. There I was standing alone and thinking, ‘Wow!’ Not only was it film history but I was going to be on Star Trek, something I’ve really enjoyed all my life." 
As a newcomer to the franchise, the regular cast made McDonough go through an initiation ritual. "Because I was the only one with the tight-fitting suit - everybody else wore these baggy suits - and this Greco-Roman haircut kind of thing going on, they called me Studbuck on the set." he recalled, "Patrick Stewart, Jonathan Frakes and all the other guys never hesitated to belittle me in front of everybody. It was the, ‘Oh, it’s young Studbuck,’ kind of thing. This started on the first day, so I knew that since these guys were making fun of me right from the start they must have really liked me." 
For the zero-gravity "space walk" scene on the ship's hull, the actors were made to put lead weights in the bottom of their footwear to make their performance look more realistic. "I remember turning to Patrick and saying, ‘We’re actors. Do they realize that we can fake it?" McDonough recalled. "Instead, we walked around for two weeks with all these weights in our boots." Despite being uncomfortable during the scene, McDonough admitted he had a "lot of fun". 
Originally, a stunt man was to be used in the scene where Hawk (as a drone) is thrown off the hull of the Enterprise but McDonough couldn't resist doing it himself. "I grab Patrick, punch him and then throw him on the floor." he recalled. "I’m just about to take my foot and plant it in his face when Worf blows me into outer space. They had stunt men all over the place and I said, ‘No, I’m doing this. I am the Star Trek man now. There’s no way that anyone else but me is going to fly through the air wearing this flying harness.’ I had such a great time." 
McDonough won the Jury Award from the Atlantic City Film Festival for his performance in the 1999 independent drama film A Perfect Little Man. That same year, he was seen in a supporting role in the film Ravenous and appeared on the series Profiler with Jeremy Roberts. In 2000 McDonough had a recurring role on Martial Law, which included one episode with Jeffrey Combs and T.J. Storm.
McDonough played 1st Lt. Lynn 'Buck' Compton in HBO's acclaimed, Emmy Award-winning 2001 mini-series Band of Brothers. His co-stars on this project included David Andrews, Scott Grimes, Tom Hardy,Simon Pegg and Douglas Spain. Band of Brothers executive producer Steven Spielberg subsequently hired McDonough for the major supporting role of Pre-Crime officer Fletcher in the hit 2002 science fiction film Minority Report. In this film, McDonough worked alongside Patrick Kilpatrick, who played a fellow Pre-Crime cop. Sumalee Montano appeared in an uncredited role and Petra Sprecher performed stunts in the film.
In 2002, prior to the release of Minority Report, McDonough appeared in two episodes of the popular science fiction series The X-Files: one with Alan Dale and James Parks and directed by Kim Manners and the other with Dale, Kerrie Keane, and Brian Morri. Later that year, McDonough became a series regular on the NBC drama Boomtown. Although this series was canceled after only one season, McDonough won a Golden Satellite Award and was nominated for a Television Critics Association Award for his performance.
In 2003, McDonough appeared in Paramount Pictures' 2003 science fiction adventure film Timeline, which also featured Stephen Liska. McDonough then co-starred with Dwayne "The Rock" Johnson in the 2004 remake of the semi-biographical film Walking Tall. During the 2004-2005 television season, McDonough starred in another drama series for NBC, Medical Investigation. Like Boomtown, however, this series was pulled after just one season.
Over the last several years, McDonough has acted in the such major feature films as The Guardian (2006, co-starring Clancy Brown), Flags of Our Fathers (2006, with Michael Canavan, Len Cariou, Gordon Clapp, David Clennon, Mark Colson, Christopher Curry, Ron Fassler, George Hearn, James Horan, and Harve Presnell), I Know Who Killed Me (2007, with Spencer Garrett, Gregory Itzin, and Brian McNamara), and 88 Minutes (2008, with Kaj-Erik Eriksen and editing by Peter E. Berger). In the 2008 sports film Forever Strong, McDonough and TNG guest star Julie Warner played husband and wife. McDonough's most recent film role was that of General Bison in the 2009 action film Street Fighter: The Legend of Chun-Li, based on the hit video game series.
In 2007, McDonough was a regular on the short-lived drama series Traveler, as were Steven Culp and William Sadler. Later that year, McDonough starred as Wyatt Cain in the Sci-Fi Channel mini-series Tin Man, working with Gwynyth Walsh. From 2008 through 2009, McDonough portrayed Dave Williams in the fifth season of Desperate Housewives, starring Teri Hatcher and narrated by Brenda Strong. On this series, McDonough's character went insane trying to avenge the deaths of his wife and daughter in a car accident which involved Hatcher's character.
Staring in 2011, McDonough began playing "Dum Dum" Dugan in the Marvel Cinematic Universe with Captain America: The First Avenger, a film based on one of Marvel Comics' best-known characters. He went on to reprise the role for the series Agents of S.H.I.E.L.D. and Agent Carter as well as a still image for Captain America: The Winter Soldier.
He also plays villain Damien Darhk , leader of H.I.V.E., in DC's Arrow 4th season (in which co-starred Janet Kidder who portrayed Damien's wife), and reprises this role in seasons 2, 3, and 5 of DC's Legends of Tomorrow as well as seasons 2 and 8 of DC's The Flash.