- "Oh, my God! The quarterback is toast!"
- ―Theo [src]
Theo was one of the terrorists and the sole computer hacker in Hans Gruber's group that attacked Nakatomi Plaza on Christmas Eve, 1988. Theo was well aware of what the group was doing and didn't seem to care much. He was depicted as weaselly, insensitive and arrogant, cracking jokes whenever people were killed. Theo and Eddie were the only American terrorists in Hans' group. He is the tertiary antagonist of Die Hard.
Theo has black hair and brown eyes.
- "You didn't bring me along for my charming personality."
- ―Theo when asked if he can 'break the code' [src]
Theo arrived at Nakatomi Plaza with Karl in a separate car he was driving while the others were in the Pacific Courier truck, heading for the underground parking lot. Once Theo and Karl arrived, he pretended to be talking to Karl about basketball to keep up appearances until Karl killed a security guard in the main desk. Theo jumps up to the desk, kicks the dead guard down and reports to Heinrich, who was driving the courier truck, on the radio that they're inside the building. He then proceeds into the building's security room and began locking down the building while humming to himself. Theo locked down the building's elevators from the 30th floor down, except for the service elevator. He then closes the parking lot gates and shut off the escalators. Theo destroys the security cameras by pulling the fuse to them and kicks over the console server. He joined Hans and the others after he completed his initial task.
After Hans and the others took control of the 30th floor, Theo went to the 34th floor conference room to try to gain access to the code and first safeguard to the vault containing $640 million in bearer bonds. Then Hans arrived with Karl, Karl's brother, Tony, and their hostage, Joe Takagi. In the room, Hans tried to get Takagi to willfully give him the code to the vault. When he refused, Theo implied to Karl that he knew Takagi wouldn't talk. Karl retorted that it wasn't over yet, as they had a bet riding on the outcome. Hans threatened Takagi with a count to three, but Takagi refused again and Hans killed him. Karl paid up, since Theo won the bet. Then, they heard a strange noise outside the conference room. Karl and Tony investigated but couldn't find anything. Hans then told Theo to break the code himself.
Breaking the vault open
- "You bet your ASS I wish to proceed."
- ―Theo after breaking the code [src]
Theo tells Hans that it will take him 30 minutes to break the code and it take him about two-two-and-a-half hours for breaking through the five mechanical locks at minimum. But he cannot cut the seventh lock, the electromagnetic seal system, since its circuits cannot be cut locally as he opened the access way to the vault. Hans tells him that they will go through with the plan. With that, he and Kristoff began working on the vault. Once he got the code to release the first lock, he began drilling the mechanical locks in the vault.
After awhile, Hans checked in with Theo, asking about his schedule. Theo says he cracked three locks and still need to work on four locks, include the electromagnetic seal. During the radio call from their intruder and the cop, Sgt. Al Powell, Theo stop drilling to listen in. After listening and knowing that they don't know their true agenda, he began drilling the vault's locks again.
Spying on the incoming cops
- "Alright, listen up guys. Twas' the night before Christmas, in all through the house, not a creature was stirring except the four assholes, coming in the rear in standard two-by-two cover formation"
- ―Theo spotting the SWAT officers in the security camera [src]
When the cops are starting to come in, Hans has Theo spy on them from the building's security cameras they took over earlier. Theo then spots four SWAT officers, coming in from the rear of the camera and wittily tells to the others about it in the Twas' the night before Christmas remark. Then he spots the armored RV coming to them on the southeast corner. Then when Alexander and James hit the armored car with a rocket, rendering it immobile, Theo cheers at the scene, saying, "Oh my god and the quarterback is toast!".
After dealing with the cops, Theo get back to work on getting the vault open. When Hans checks him in after learning the identity of their intruder John McClane and making a fake demand to release his comrades-in-arms around the world, Theo tells him he has one more lock to deal with and the last one will take the miracle. Hans tells to call him when he hit the last lock.
Getting the vault open
- "Merry Christmas."
- ―Theo in awe when the vault finally opens [src]
After breaking the last mechanical lock, Theo checks in with Hans about him hitting the last lock and the electromagnetic system came on immediately. Hans tells him to look at what the police are doing outside and he'll be right up there. Theo shows Hans that the cameras shows the city engineers and that they are going to the street circuit. He also sees men in the suits, which he doesn't know who they are. Hans tells Theo those men are the FBI and that they are ordering the others to cut the building's power, which Theo now realizes it will shut off the electromagnetic lock in the vault. Hans says that circuits that they cannot be cut are cut automatically in response to a terrorist incident and that the FBI are having the building's power cut.
When the building's whole are grid was turned off, the electromagnetic lock was shut off and that the vault was finally open. Hans, Theo and Kristoff we're awed by the sight of the vault and Theo smiles in celebration. As he was opening the cases that carry bearer bonds, Theo happily celebrates that they are going to be rich.
While he and Kristoff were loading the bearer bonds in bags, Hans arrived with Eddie and hostage Holly Gennero-McClane, identified as the wife of McClane which is then reveal to them by reporter Richard Thornburg who interview her daughter Lucy. Theo arms the C4 explosives that are on the roof. He heads for the garage to get the ambulance loaded inside the Pacific Courier truck ready. He went into the truck and put on a paramedic's uniform disguise before heading into the back of the truck and backing out an ambulance. However, this inadvertently caught the attention of John McClane's limo driver, Argyle, who had been locked into the garage when Theo closed the gates to keep everyone out of the building. Argyle started the car and drove around, to discover that Theo was attempting to set up their escape route. Argyle snuck up on Theo and gunned it, ramming his limo into the ambulance's side. As a result of the impact, Theo was momentarily stunned; before he fully recovered, Argyle got out of the limo and punched him in the face, breaking his glasses and knocking him out. Theo was not seen after this incident and his fate was left unknown, but it can be inferred that he and perhaps Kristoff, who was possibly knocked out by McClane, was found by the police and arrested. He was the only terrorist to have definitely survived and not to have encountered McClane.
Theo had a very snarky and laid back attitude to the Nakatomi takeover. He was constantly making jokes and witticisms during inappropriate moments to lighten the mood. He was also a sports fan as he makes references to American football and basketball at certain points in the film. The only person he's shown really conversing with throughout the narrative is Hans, though he's also shown to have made a bet with Karl about whether Takagi would give up the code to the vault. Theo is rather despicable because he has absolutely no problem with people dying, often cracking jokes as people are killed.
In a shortened scene, Hans Gruber asks Theo if he can crack the code to the vault. Theo responds that he didn't come along for his "charming personality". As Hans walks away, he quietly says "Though you could have".
- Clarence Gilyard (Theo) was actually punched by De'voreaux White (Argyle), in the escape attempt scene. White said McTiernan and the crew wanted to see a real actor pull it off because the last takes were not realistic.
- Theo's role as the most intellectual member of the group is oddly prophetic, as Clarence Gilyard later retired from acting and became a college professor.
- He and Eddie are the only American members of Hans' gang.
- Theo is the only member of Hans Gruber's gang to be African American. He is also the first African American antagonist of the Die Hard movies.