Road to La Gias

"“Brian and Stewie's ultimate Family Guy adventure continues, this time below the surface!” ―Tagline"Road to La Gias is the twentieth episode and season finale of the 18th season of Family Guy, as well as the 349th overall episode. It is the tenth installment of Family Guy's Road to... series and the sequel to Road to Eostia, which aired earlier in the same season, and like the aforementioned episode, it is a 90-minute TV movie that spans four parts and aired on Fox in the United States on May 24, 2020 without commercial interruption. The episode was directed by Greg Colton and written by Danny Smith.

The TV movie follows Brian, Stewie and Chris, as they discover Carter Pewterschmidt and Bian Zoldark negotiating and heading to an unknown location, and upon following them, enter into a mysterious underground world of La Gias.

Upon broadcast, the special was met with generally positive reviews like its predecessor and viewed by 9.98 million homes across North America according to Nielsen ratings. It also serves as a crossover in some regards with Thomas & Friends, featuring characters from the show.

From Sodor to Wherever
While the Griffins are on a family trip in Sodor, England, Brian and Stewie suddenly spot Bian Zoldark and Carter Pewterschimdt having a conversation in the same station. When the two men get inside the train Thomas, Brian and Stewie decide to follow them and ride on the train without getting caught, with Chris stowing away with them, stupidly thinking the truck of coal Thomas carries is a toilet. As the three continue to ride along the train, they come across a very unfamiliar railway which leads to an underground tunnel that keeps going down for several minutes until the descending slope stops and they see the light. When the train leaves the tunnel, Brian, Stewie and Chris are awestruck to find themselves into a new, completely different and magnificent city with massive sky-high towers, beautiful landscapes and wondrous locations.

Welcome to La Gias
When the three get off the train, they get caught by the city's guards. Carter is shocked to see them and pardons them since they're his family. They are welcomed to the Kingdom of Langran, the most prosperous kingdom in the underground world of La Gias.

Adjusting
Unfortunately, for the people of Langran, Alzarl was killed in a terrorist bombing in the Royal Palace. After his death, the Langranian government pinned the blame to the Shutedonias, a faction that the Kingdom of Langran has a long cold-war-like rivalry against.

Carter's True Intentions
An enraged Brian asks the corrupt businessman why he abducted Monica and what his endgoal is. Carter revealed that he had Monica kidnapped not only to escalate the La Gias cold war into an all-out conflict, but also use her as a blackmail ploy to force the leaders of Langran to purchase weapons of mass destruction that he had kept in his Industries for a time, becoming a private supplier of weaponry to the Langranian military and keeping both the spoils of both Earth and La Gias to himself.

Main Characters

 * Brian Griffin - The family dog and the voice of reason of the Griffins.
 * Stewie Griffin - The baby supergenius and Brian's best friend.
 * Chris Griffin - Stewie's stupid 14-year-old brother.

Sodor, England

 * Sir Topham Hatt - Known generally as "the Fat Controller", he is the owner of the North Western Railway in Sodor.
 * Thomas the Tank Engine -
 * Percy the Small Engine -
 * Gordon the Big Engine -
 * James the Red Engine -
 * Donald and Douglas -

Kingdom of Langran

 * Feilord Gran Birseia - The prince-heir of Langran who became king in his late father's place.
 * Monica Grania Birseia - The younger sister of Feilord and the princess-heir to the Langranian throne. She develops a romance with Brian throughout the special.
 * Senia Grania Birseia - Monica's twin sister and a headstrong tomboyish engineer.
 * Alzarl Gran Birseia - The former King of Langran who was killed in a terrorist attack conducted by Lubika Hakkinen on behalf of the Shutedonias.
 * Tellius Gran Birseia - Feilord's weak-willed cousin.
 * Elan Zenosaxis - A distant relative of the Zenosaxis noble family and a "God hunter" as he calls himself to be.
 * Kirkus Valfabia - A general and right-hand man of Feilord.
 * Zashford Valfabia - The son of Kirkus.
 * Ivanov Kozireh - An ex-KGB Russian officer who was recruited within the Langranian army.
 * Nico Sandriff - An idol singer and defector from Shutedonias.
 * Rico Sandriff - Nico's identical twin sister.

Republic of Bagonia

 * Gino Valencia - A Duke and one of the leading military leaders of Bagonia, though he acts very calmly and composed as opposed to others.
 * Rosalie Shemuel - An adventure-seeking cowgirl.

Republic of Almera

 * Lionel Nielsen - A stubborn Canadian Navy Seal who somehow finds himself fighting for Almera.

Pewterschmidt Industries

 * Carter Pewterschmidt - The father of Lois Griffin and the multi-billion owner of a massive worldwide business empire, which includes the Pewterschmidt Industries. He also serves as the special's main villain until the third act, being much more antagonistic than any of his prior appearances.
 * Bian Zoldark - President of the United Nations General Assembly who made a secret agreement with Carter.

Shutedonias Alliance

 * Rodney Jesh - The commander-in-chief of the Alliance's army.
 * Elis Radius - Rodney's wife.
 * Lubika Hakkinen - A Finnish Neo-Nazi who was hired and paid by the Shutedonias to commit acts of terrorism in Langran.
 * Lasett Novaste - The Supreme Chancellor of the Alliance.
 * Mudeca Lavence - A devout nationalist of Shutedonias.

Cult of Volkruss

 * Luozorl Zoran Roiel - The High Priest of the Cult.
 * Wuuf - A mercenary-for-hire, paid by Luozorl to assassinate Stewie, Brian and Chris.
 * Pierre Boarasen - A mad scientist within the ranks of the Cult.
 * Sava Volkruss - The movie's true antagonist and the Dark Evil God of La Gias, a monstrous entity that all creatures of the underground world fear more than anything else.

Other Characters

 * Peter Griffin
 * Lois Griffin
 * Meg Griffin
 * Dr. Elmer Hartman
 * Tom Tucker
 * Joyce Kinney
 * Barbara "Babs" Pewterschmidt
 * John Herbert

Other Pages

 * Road to Eostia (season premiere)
 * Road to Balmar (Season 19 finale)
 * Road to the End of the Galaxy (Season 20 and series finale)