William Shatner began his outside-the-box musical career in the 60s, recording spoken-word versions of rock hits. In the 2000s, he resumed his recording career, and ever since it has taken him into strange, unexpected territory, with a head-scratching array of collaborators including Henry Rollins, Joe Jackson, Lyle Lovett, Sheryl Crow, Steve Vai, and many more. This year even saw the release of a Shatner Christmas album.Shatners musical moonlighting began while he was still inhabiting the role that would define him for generations of fans: Star Treks Captain James T. Kirk. His 1968 album The Transformed Man found him delivering dramatic, spoken versions (with musical backing) of some of the most popular songs of the era, like Bob Dylans "Mr. Tambourine" and The Beatles "Lucy in the Sky with Diamonds." Was he delivering these out-there performances in earnest or with a broad wink? To this date, thats never really been determined, but that nebulousness has always been part of the fun.It took until 2004 for the always-busy actor to finally follow up The Transformed Man. His second album, Has Been, opened with his version of Pulps "Common People," and the rest of the record was occupied with original material, mostly co-written with Ben Folds, that found Shatner doing duets with everyone from Henry Rollins ("I Cant Get Behind That") to Brad Paisley ("Real"). Has Been turned out to be a surprise hit, and it earned such a rapturous reception that Shatner was inspired to embrace music more wholeheartedly than ever before. A string of albums followed over the next several years, each one demonstrating both his eclecticism and his willingness to go out on a limb. In retrospect, its hard to believe it took him so long to tackle the concept of Seeking Major Tom, an album of outer space-themed rock classics like David Bowies "Major Tom," Elton Johns "Rocket Man" (a song hed famously done live on TV but never recorded before), and Duran Durans "Planet Earth."Ponder the Mystery took the trippy themes a step further, as producer Billy Sherwood of Yes helped Shatner create an appropriately interstellar-sounding prog rock album that featured contributions from artists associated with Tangerine Dream, Hawkwind, Frank Zappa, and other art-rock outfits. Never one to be pigeonholed, Shatner followed that cosmic outing with a country album, Why Not Me, co-helmed by Jeff Cook of country superstars Alabama, with original tunes featuring guest appearances by Neal McCoy and Cash Creek.For 2018, Shatner took a simultaneously traditional and typically confounding turn on Shatner Claus, a Christmas album unlike any other. After all, where else are you likely to hear his old pal Henry Rollins shouting along with "Jingle Bells" or Iggy Pop crooning on "Silent Night?"