Prog: the final frontier ... of William Shatner's recording career, that is.

The wily showbiz veteran, whose periodic musical outbursts stretch back to 1968's 'The Transformed Man' and include 2004's Ben Folds-produced 'Has Been' and 2011's star-studded 'Seeking Major Tom,' has chosen to delve into prog for his latest album, titled 'Ponder the Mystery.'

Due Oct. 8, the new LP finds Shatner working alongside an eclectic assortment of famous names, including Steve Vai, country star Vince Gill, smooth-jazz legend Dave Koz, Foreigner's Mick Jones, Nik Turner of Hawkwind, Edgar Winter and Robby Krieger of the Doors. The set also boasts a heavy Yes connection -- it features an appearance by the band's former keyboard player, Rick Wakeman, and was produced and co-written by Billy Sherwood, who served in a multi-instrumental capacity for the band during the '90s.

Calling the record "a match made, if not in heaven, then in the most glorious reaches of the galaxy," the label's press release explains Shatner's prog excursion: "Shatner is after all an enormously popular and celebrated icon of science-fiction fantasy, and no musical genre is as invested in, devoted to or driven by fantasy and the imaginative as progressive rock." (As Shatner himself put it to Rolling Stone, "I'd love to be part of a discussion of where progressive rock ends and country music begins.")

He'll be taking that discussion on the road with a short burst of tour dates, starting Oct. 23 in Hermosa, Calif., and ending Oct. 25 in San Juan Capistrano. And who knows? There might be more in store for hungry Shat fans. "I'm feeling the audience out to see whether it's as good as I think it is and whether we should go on with it or not," he said in a recent interview. "In effect, Hermosa Beach is a testing ground. This is a new experience for everyone."

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