Tom Fargood aka Alexander Gallos appears in Harbingers in the Fountain. He is the Mass Murderer who founded the group, Harbingers of a New Day which consisted of people with MCS (Multiple Chemical Sensitivity). He claims to have built an underwater hotel in French Polynesia called Harbinger. Fargood had a Navy suit which was used by Navy Seals who work in submarines to make the people in the group believe that he works in a submarine. He gave the people in his group certificates with gold seals that he applied himself whenever they passed part of his training. For example, using a spear gun to hunt fish. He used antifreeze to kill eleven people in the group and used a spear gun to kill a 12th man named Louis Lampcov. Fargood gained almost a million dollars from each person he killed. He, along with his associate, Dr. Leacock, transported their bodies with a rental van and buried them under the Teversham Fountain during its renovations. Fargood got rid of the van, spear gun, and his Navy Suit or poopie suit. Avalon Harmonia was able to use her cards to locate the bodies after ten years. During those years, he changed his name to Alexander Gallos and started to work on having elderly people place non-refundable deposits for an exclusive retirement community. He planned to kill those people for their money just as he did when he killed every remaining person in the group Harbingers of a New Day. Brennan and Booth needed to prove that Gallos was Fargood since his identity was 'bullet-proof' according to Caroline Julian. They had Fargood's DNA from the saliva on the gold seals on Avalon's Harbinger certificate. Booth manipulated Avalon to attack Gallos to get his blood since Gallos killed her sister, Jenny James. Dr. Saroyan proved that Gallos' blood is a perfect match for Fargood's DNA. Regardless of proving that Gallos was Fargood, there was not one piece of evidence that proved that Fargood killed those twelve people since the antifreeze poisoning was untraceable.
However, prosecutor Caroline Julian determined that while it was impossible to get Fargood for murder, he had committed numerous other crimes. Amongst these crimes was grand theft auto for stealing the rental van, fraud by wire for selling a hotel under the sea that he can't prove exists and illegal wearing of the uniform for using Navy issued suits. According to Caroline, these are just the federal crimes that Fargood can be charged with. Caroline gets the DA to compile his own list of state charges against Fargood. Together, they will put him in prison for "a hundred years, give or take."
In front of Avalon, Booth places Fargood under arrest, telling him that they have a whole list of charges for Fargood. While they can't get Fargood for murdering her sister, Avalon accepts it as the second-best option.