|Real Name||Andrew Laurence|
|Born||1st September 2033|
|Role||Spectrum Field Agent, Senior Staff Officer, and Colour Code Captain|
|Voice Actor||Gary Files|
He was a Spectrum agent who disguised as a waiter during at the first Spectrum Intelligence conference. Hoping to infiltrate the conference, the Mysterons used Captain Black to assassinate him. Indigo was then reconstructed into a Mysteron Agent .
Indigo's cover was blown by General Peterson using the C38 Detector. Indigo set the master controls of the hunting lodge down, crushing the underground conference room. Captain Scarlet and the 2nd Warden gave chase, not only saving the delegates but providing a practical use of the Mysteron Gun.
Captain Indigo was voiced by Gary Files.
- Captain Indigo's puppet had previously appeared as Macey in Big Ben Strikes Again and went on to appear as the Rocket Room Controller in Renegade Rocket and Mervin Brand in The Launching.
- It appears in Joe 90 as Nurse John in Operation McClaine, the Shop Assistant in Business Holiday, Kent in Most Special Astronaut, the 1st Russian in Arctic Adventure, Mike Laramie in The Fortress, the Driver in Project 90, a Prisoner in The Professional and Dr. Slade in Test Flight.
- In The Secret Service, it was used as the Highway Police Officer in A Case For The Bishop, a Helijet Pilot in To Catch A Spy and Mark Slater in The Deadly Whisper.