Captain Black is the fictional nemesis of Captain Scarlet and recurring Mysteron agent in the 1960s British supermarionation science fiction television series Captain Scarlet and the Mysterons and its rendered 3D remake Gerry Anderson's New Captain Scarlet.

"Captain Black" is a code name; his real name is never revealed in the series, although subsequent publications have given this as Conrad Turner. His transformation from human to Mysteron agent occurs on Mars in the first episodes of both the original and new series; "The Mysterons" and "Instrument of Destruction Part 1" respectively.

Captain Scarlet and the Mysterons

Captain Black Zero X mission

Captain Black leading the Zero X mission to Mars.

Captain Black began his duties for Spectrum and helped create the organisation and the construction of the it's main headquarters Cloudbase, he soon became known as one of Spectrum's best agents. Unlike the other Spectrum agents, the lining of his jacket and belt were white in contrast to all the other agents' lining being black. He showed great passion and determination and was close friends with fellow agent Captain Scarlet.

Black was sent from Spectrum to lead the second Zero-X mission to Mars after hearing strange radio signals back at the base. Until then, humankind was aware only of rock snakes (featured in Thunderbirds Are GO) inhabiting the planet. Consequently, Black was shocked to find an alien city on the Martian plains. When the complex home to an alien intelligence known as the Mysterons turned a scanning apparatus onto his Martian Exploration Vehicle (MEV), Black panicked by misinterpreting it as a weapons system and, believing the city to be hostile, ordered his subordinates to launch an full scale attack on the complex.

Afterwards he stared in amazement at the Mysterons' ability of reconstruction on their city and the aliens swore vengeance against Earth for what they saw as a unwarranted act of aggression. They seized control over Black's mind as a punishment and used him as an instrument in their "War of Nerves" against the Earth. In the TV21 comic the Zero X was sent returning to Earth (although the fate of the crew left in the orbiting main body was never disclosed), Captain Black returned to Earth as the only survivor and wasn't seen again, Colonel White mentioned him as a trusted man and has no idea what happened to him.

Captain Black since having his mind taken over by the Mysterons has his body changed, his face has turned very pale and his voice has been taken over by the Mysterons turning it very deep, Captain Black is only shown wearing his Spectrum uniform in the first episode and the opening in the episodes after, he is normally seen in black civilian clothing to match his new character.

Through Captain Black, the Mysterons relay instructions to other agents on Earth and compel him to undertake acts of terrorism and murder through their disembodied voice. However, even under the influence of the Mysterons, Black is not completely devoid of humanity. For example, after becoming a radioactive hotspot in the episode "Manhunt", he captures Symphony Angel while hiding from Spectrum and subjects her to lethal radiation inside an atomic centre, but desists before she is killed and allows her to escape. While Spectrum agents chase after an SPV, which they believe contains Black but is actually being driven by Symphony, he decontaminates himself inside the atomic plant and thus avoids Spectrum's attempts to detain him.

In the episode "Treble Cross", an Air Force test pilot unexpectedly survives an assassination attempt by the Mysterons and helps Spectrum in another effort to catch Captain Black. However, he is not deceived when the human pilot replaces his own Mysteron duplicate and evades Spectrum for a second time, suggesting that the Mysterons have equipped him with a "sixth sense" which can warn him of danger.

Black can also teleport if under threat of capture. This occurs in the episodes "The Heart of New York", "Model Spy" and "Inferno".

Gerry Anderson's New Captain Scarlet

Captain Black

Captain Black as he appears in 2005 Captain Scarlet.

There are several differences between the original Captain Black and that of the new series. For example, his last name is Lefkon, as shown on his gravestone in the first episode. Before his Mysteronisation he is shown as a much more sympathetic character, and his destruction of the Mysteron city now seems far more reasonable as his vehicle's equipment actually identifies the Mysteron probe as a weapon. In contrast, after Mysteronisation he is an almost stereotypical villain, taking pleasure in the acts of murder that he commits. At one point, he even leaves Captain Scarlet chained up in front of his latest doomsday device, complete with digital countdown. However, on occasions (for example in the episode 'Best of Enemies') Scarlet has been able to educe Black's original personality, and may have been close to being able to break the Mysteron conditioning.

In 'Dominion', the final episode of the series, Black is knocked unconscious in an attempt to destroy a nuclear facility. When he regains consciousness, he claims to have escaped the Mysterons control, and asks Scarlet to return with him to Mars to launch an attack on the Mysteron city. Although the attack is successful, the Mysterons regain control of Black. The final image of the series is of Black looking at Scarlet's departing ship, then walking away. Two green rings follow him, catch up and Black vanishes.

The voice of the new Black is the same as before Mysteronisation, save when the Mysterons take direct control of his body.