Josh Edge, Alaska Public Media

The 2010 eruption of the Eyjafjallajokull volcano in Iceland provoked economic chaos by paralyzing a major air traffic network for days. This eruption, however, was mild. Much more powerful volcanoes in Iceland are ready to wake up. Through spectacular aerial footage of this country, which is an accumulation of lava and ash, a maze of craters and faults, the episode tries to discern which volcano could wake up next and what the consequences of a major eruption are likely to be. Europe has come to realize that a colossal power sleeps beneath Iceland, while Icelanders for centuries have learned to live amongst their volcanoes. TV: Wednesday, 1/2 at 9:00pm

From the U.S. television debut of the Beatles in 1964 to the Doors’ infamous one-time-only appearance, “The Ed Sullivan Show” brought the greatest musical acts in the world into America’s living rooms every Sunday night. This new MY MUSIC special features both the Beatles and the Doors as well as memorable performances from other superstars of the 60s pop-rock era, including the Mamas & the Papas, the Rolling Stones, Johnny Rivers, the Beach Boys, Tom Jones and Creedence Clearwater Revival. TV: Tuesday, 1/1 at 8:30pm

Season 2 of "Downton Abbey" concludes with the family gathering at Downton for Christmas and the New Year; and Bates on trial for the murder of Vera. In other events, Robert offers relationship advice to Mary. TV: Sunday, 12/30 at 8:00pm

Uncover the story of the first quintessentially American dance company, the Joffrey Ballet. Founders Robert Joffrey and Gerald Arpino pioneered a new dance philosophy by daringly combining modern and traditional techniques and art with social statement, and integrating pop and rock music scores. Tracing the struggles and triumphs of the company from 1956 to the present. TV: Friday, 12/28 at 9:30pm

Lisa Kudrow hosts a two-part special that reveals the crucial impact of the arts on the human brain across a lifetime and explores their vital role in human development during youth and age. The programs show how music, dance, painting, poetry and theater markedly improve well-being at both ends of life and reveal the cutting-edge science that explains the powerful, positive impact of the arts on the brain. TV: Thursday, 12/26 at 7:00pm

Carved from a hundred million pounds of stone, soaring effortlessly atop a spider web of masonry, Gothic cathedrals are marvels of human achievement and artistry. But how did medieval builders reach such spectacular heights? Consuming the labor of entire towns, sometimes taking a hundred years to build, these architectural marvels were crafted from just hand tools and stone. Many now teeter on the brink of catastrophic collapse. To save them, an international team of engineers, architects, art historians and computer scientists searches the naves, bays and bell-towers for clues to how the dream of these heavenly temples on earth came true. TV: Wednesday, 12/26 at 8:00 p.m.

"Downton Abbey" continues with the Spanish flu sweeping through the household and infecting Cora, Lavinia and Mr. Carson, among others. Mary, Sybil and Robert, meanwhile, each face a moment of truth. TV: Sunday, 12/23 at 8:00pm

Julie tells PC Mylow that she's pregnant; Louisa has doubts about moving in with Danny, so Aunt Joan asks Martin to intervene. TV: Saturday, 12/22 at 7:00pm