his investigation uncovers a conspiracy within his old agency. In the sixth and most recent game, Blacklist, Third Echelon has been disbanded by the President of the United States. A new outfit, Fourth Echelon, is formed by the President and placed under the command of Fisher with the mission of stopping the 'Blacklist' attacks and the Engineers, the organization behind them. Blacklist deals with the morality of war and how far Fisher and his team go in order to prevent these plots against America. Trifocal goggles A device used for seeing in the dark features strongly in the series. Originally, Tom Clancy had rejected the idea of Fisher having these "trifocal goggles", having stated that such goggles (with both thermal vision and night vision) were impossible to make. The creators argued that having two separate sets of goggles would have made for awkward gameplay and convinced Clancy to allow it. This also gave the Splinter Cell series a recognizable signature, a desirable feature. Chaos Theory added a third one, electromagnetic view, which shows the path of electricity in the area, mainly electrical cables and any device that has electrical power, like TVs, computers, etc. Conviction allows a fourth module to be accessed, a sonar module that can scan through walls for interactable objects, such as weapons, people, and consoles. The trifocal goggles however, didn't remain completely fictional. In 2004, Northrop Grumman produced and delivered one such device. The device, called Fused Multispectral Weapon Sight (FMWS) was capable of combining thermal and intensified imaging. Later in 2007, ITT Industries developed another such device, designated AN/PSQ-20. Characters The characters of the games, as well as the organization "Third Echelon", were created by J. T. Petty. The main recurring ones are: Sam Fisher is the main protagonist of the series. The character ranks 24th on the "Guinness Top 50 Video Game Characters of All Time" list. Irving Lambert, leader of "Third Echelon", serves as the player's guide by leading Fisher through the games' missions, until he is killed by Sam in Double Agent. Anna "Grim" Grimsdóttír is portrayed as an official Third Echelon hacker and analyst, who helps Fisher when technical obstacles need to be overcome. In Conviction she takes over the role of guide from the deceased Lambert; her character also becomes the source of dramatic tension in the story. In Blacklist, she is the technical operations officer and butts heads with