Part history lesson, part outdoor escape room, History Colorado’s “Mystery Quest” is about to set adventure-seeking history buffs off on a Denver-wide, episodic scavenger hunt from Sept. 3-19.

Organizers call the returning favorite an opportunity for Denverites to discover their city through new eyes and ears by embarking on a self-guided, COVID-conscious journey to unravel the mysterious legacy of a local academic named Astrid Lee.

Volume 2 of “Mystery Quest,” which debuted last summer, begins with registered groups being provided with a dossier made up of sequential clues, each leading to puzzles spread throughout the city.

So who was Astrid Lee? According to the creators, she was an author who in the 1960s began writing a book called “Always Something There to Remind Me” (not to be confused with the 1983 song by Naked Eyes.) The book was never published, but the young historian is said to have “discovered a secret Denver” in her research. Parts of her manuscript, so they say, were unearthed at a construction site in the summer of 2019. One that included her radical theories about democracy, socialism, civil rights, labor, migration and even UFOs.

”Mystery Quest” is organized by History Colorado’s Chris Getzan and creative influencer Andrew Novick in collaboration with Barry Osborne of Swallow Hill Music.

Getzan claims Lee set her budding book aside in 1973 after the bombing of Cambodia left her with no hope for democracy. He says she disappeared completely in 2018, but when a building got knocked down off of Bannock Street the next year, her manuscript was found in a footlocker at the site.

How much of that origin story is actually true and how much just makes for great historical drama? Says Getzan cryptically: “The best things in life we get from professional wrestling. And pro-wrestling teaches us to never break kayfabe.” Regardless, the intriguing premise allows the creators to marry fiction with fact through the legacies of actual Denver revolutionaries, reformers, artists, comics, storytellers and poets.

“Think ‘The Goonies’ meets ‘Where in The World Is Carmen Sandiego’ with a dash of ‘Twin Peaks,’ all right here in Denver,” said Getzan. “This year’s quest is all about cooperation and coming together to unravel the past. And I guarantee you’ll learn something new – whether you like it or not.”

“Mystery Quest” also integrates contributions from local musicians Distance Walk, Felix Fast4ward, Michelle Rocqet of Milk Blossoms, and MC Kalyn Heffernan of Wheelchair Sports Camp; along with original creations by Denver artists Lonnie Allen, Don Austin, Roxann Diffin, Emily Hope Dobkin, Cassandra Elaine, Thea Hunt, Cori Redford, and students from Arts Street.