Master Sergeant MacDonald James "Mack" Gerhardt (United States Army, callsign: Dirt Diver) is a fictional character on the CBS television series The Unit. He is portrayed by Max Martini. Is a former Army Ranger and a senior Unit operator. He holds the rank of Master Sergeant (E-8). His wife, Tiffy, and he have two daughters.
Gerhardt worked with Jonas Blane and his team on the recovery of a radioactive component of a Chinese satellite, rescuing the drug minister of Mexico, the assassination of a terrorist financier in Spain, the bugging of an Iranian official's car at their embassy in Beirut, the recovery of seven Stinger missiles from Brazilian arms dealers, and the apprehension of a Serbian war criminal in The Balkans.
While in The Balkans, the war criminal Gerhardt's apprehended got a good look at Jonas Blane. When the criminal escaped from UN custody, he tracked Blane back to Fort Griffith, the 303rd's headquarters. When Alpha Team went off post to celebrate the marriage of Unit commander Colonel Tom Ryan, the war criminal struck, killing a few workers and injuring Mrs. Ryan and Jonas Blane.
A few months later (during Season 2), Gerhardt prepares to leave the Unit, but Tiffy decides to rescind her request, ripping up Gerhardt's transfer papers. Since then, he has helped take down the world's foremost weapons dealer, and has helped taken out a rebel leader in Paraguay.
Gerhardt is a former Army Ranger and is now the assistant team leader of Sergeant Major Jonas Blane's Alpha Team of the 1st Special Actions Group (official cover as the "303rd Logistical Studies Group"). He is competent in Italian and German; and while competent at submarine lock in/lock-out procedures, is slightly claustrophobic. He and his wife, Tiffy Gerhardt, have two daughters.
Gerhardt has worked as an operator with Blane and his team on a multitude of missions, including the recovery of a radioactive component of a Chinese satellite, the rescue of the drug minister of Mexico, the assassination of a terrorist financier in Spain, the bugging of an Iranian official's car at their embassy in Beirut, the recovery of seven Stinger Missiles from a Brazilian arms dealer, and the apprehension of a Serbian war criminal in the Balkans.
During the 3rd episode of Season 1, 200th Hour, Mack is accidentally shot during a live fire training course by Bob Brown. It is later discovered that the incident occurred because Mack had entered Brown's sector without Brown noticing.
During the 7th episode of Season 1, Dedication, Mack is offered charge of his own team by Ryan, but turns the offer down. Instead wanting to continue serving with his friend Jonas.
At the end of season 1, the apprehended war criminal, a Yugoslavian General named Razlan Dragovich, got a good look at Blane and suspected him of firing the shot that killed Dragovich's wife. When Dragovich escaped UN custody, he tracked Blane back to Fort Griffith, the Alpha Team's headquarters. When the team and their families went off post to celebrate the marriage of Unit commander Colonel Tom Ryan, Dragovich and his men attacked. They killed several restaurant employees and injured both Blane and the new Mrs. Ryan.
A few months later (during Season 2), Gerhardt prepared to leave the Unit at the behest of his wife, but Tiffy decided to rescind her request and ripped up Gerhardt's transfer papers. Since then, he has helped take down the world's foremost weapons dealer, and helped take out a rebel leader in Paraguay.
In the episode Johnny B. Goode, Mack and the team are in Iran to determine its Weapons of Mass Destruction capability. Mack kills a herder who would have compromised the mission, as well as their local contact after an explosion's debris pinned her to the ground to spare her from imminent capture, torture and death. When he returned home, he and Tiffy bickered, and Mack went to a bar to blow off steam. While there, he assaulted a civilian before being guided out by Crystal Burns, the fiancée of a former Alpha Team staffer. Crystal offered to drive Mack home, and commented on how screwed up the both of them were, as Crystal's fiancée had recently suffered an extensive traumatic burn injury and she was incapable of standing by him. Crystal then kissed Mack. He resisted at first, but gave in, and the two had a one night stand in the front seat of her new Mustang.
Later on, Crystal threatened to divulge the affair to Tiffy if Mack didn't continue the affair. This did not faze him, and he ordered her to go back to Jeremy and to stay away from him.
At the end of the 2nd Season, Gerhardt and Williams are placed in prison for unnamed actions which they committed on a mission. Brown manages to escape this fate by becoming a double agent to the CIA; while Grey disappears and Blane goes into hiding.
At the start of the 3rd Season, Gerhardt is brutally tortured by the CIA, but later released soon after other team members threatened members of the CIA.
Patches, tabs and badgesEdit
- 101st Airborne Division
- 24th Infantry Division
- Ranger Tab
- Combat Infantryman Badge
- Master Parachutist Badge
- Air Assault Badge
- Army Diving Badge
Awards and decorationsEdit
-  Silver Star
-  Bronze Star
-  Purple Heart
-  Meritorious Service Medal
-  Joint Service Commendation Medal
-  Army Commendation Medal
-  Army Achievement Medal
-  Army Good Conduct Medal
-  National Defense Service Medal
-  Armed Forces Expeditionary Medal
-  Kosovo Campaign Medal
-  Global War on Terrorism Expeditionary Medal
-  Global War on Terrorism Service Medal
-  Humanitarian Service Medal
-  Army NCO Professional Development Ribbon
-  Army Service Ribbon
-  Army Sea Duty Ribbon