Four years in the making, Assassin’s Creed Origins takes gamers back to ancient Egypt with composer Sarah Schachner setting the tone. The Ptolemaic-era setting was at the request of fans polled in 2011 as to where they’d like to see the time-traveling series land. Schachner’s return to the Ubisoft franchise for this third installment seems inspired by popular demand, too, after well-received turns on 2014’s Assassin’s Creed Unity and 2013’s Assassin’s Creed IV: Black Flag.

The stakes couldn’t be higher. Assassin’s Creed is Ubisoft’s top franchise, surpassing 100 million units sold as of 2016, according to the company. This tenth title in the series follows a two-year hiatus that has created great expectations from a base built around an annual release schedule.

“Sarah is a triple threat: a great composer, arranger and performer,” Ubisoft music supervisor Simon Landry told Billboard. “This allowed her to develop a unique signature that combines authentic elements from the game’s time period with contemporary music scoring.” That approach meshes well with the game -- a mash-up of historical fiction with the latest in visual storytelling and interactive techniques.

The Assassin's Creed Origins Original Soundtrack is available simultaneously with the game on Oct. 27, via all major downloading and streaming platforms for $9.99. Billboard exclusive premieres five tracks in full below.

Schachner is no stranger to time travel. She pirated the high seas with her mentor, BrianTyler, for Black Flag, playing multiple instruments and contributing additional music. As sole composer, she tackled Baroque classical for the French Revolution action of Unity and hurtled into the future with Activision’s intergalactic Call of Duty: Infinite Warfare. In the midst of it all, HBO chose Schachner’s Unity theme, “Rather Death Than Slavery,” for the season five trailer to Game of Thrones. (Batting one back across the net, Ubisoft features Leonard Cohen’s “You Want it Darker” on the Origins trailer.)

“The interesting thing about Origins and B.C. Egypt is we don’t actually know what the music really sounded like,” Schachner told Billboard on the eve of Origins’ release. “Historians and archaeologists have ideas, and can make assumptions based on later time periods and what is known about instruments of the region, but it's not like we have recordings.” For Schachner, who performed all the music herself, that was an invitation to let her imagination roam. “I wanted to create a hybrid sound of old and new with an air of ambiguity and mystery to represent this otherworldly culture that was so immersed in mythology,” she explained.

The action plays out circa 50 B.C., with Julius Caesar and Cleopatra in supporting roles as the story explores the ongoing battle between the Brotherhood of Assassins, who believe in peace through liberty, and a secret cabal suggestive of the Templar Order, who pursued peace through imposed order. To support the premise, Schachner improvised, pairing a “Blade Runner-esque” CS-80 synthesizer with ancient instruments that “always bring you back to the sand.” These include the oud, a modern relative of the fretted, plucked lutes of the time, and lyres, bells and winds, all “processed in ways to make them less obvious, as the focus was more on custom sounds and the feelings they evoke.”

With rich historical material to explore, Schachner doesn’t expect to tire of adventuring among Assassins anytime soon. “Each entry is a fresh creative opportunity to do something new, so as a composer, returning to the series never feels tiring or stale. The sci-fi context makes it even more amazing allowing you to interpret the music of the period in your own way and give it a unique voice.”

Schachner gave voice to a bit of period gaming. Her “Ezio’s Family: Origins Version,” the closing to her 27-track recorded score, is an update on the iconic theme the first Assassins composer, Jesper Kyd, originated in 2009. “There is so much beauty in these games, to provide the emotional context is the best part,” she said.

In addition to her video game work, Schachner made her solo film score debut with 2015’s The Lazarus Effect, starring Olivia Wilde, Mark Duplass and Donald Glover. Recently she contributed to the Cassini Finale Music Project, a trilogy celebrating the end of the Cassini Mission from NASA Jet Propulsion Laboratory.

Assassin's Creed Origins tracklisting: