Following a year that saw both a collaborative album with mandolinist David Grisman and a live album from the Ryman Auditorium, Australian acoustic guitar hero Tommy Emmanuel returns to his Music City muse with Accomplice One, a duets album with a strong Nashvillian flavor. Coming in at a rather lengthy 16 tracks, one gets the feeling that many of these sessions yielded more fruit than could fit on one disc, leaving the door open for future explorations and inspired pairings. Emmanuel's sparring partners here range from similarly virtuosic instrumentalists like nimble blues-rock guitarist J.D. Simoand ukulele master Jake Shimabukuro to country singer/songwriters like Suzy Bogguss and Rodney Crowell. Warmly captured in various studios in and around Nashville, Accomplice One offers a fairly wide swath of what Emmanuel and his friends have to offer, from the tasteful-but-sprightly Celtic airs and reels of the Clive Carroll collaboration "Keepin' It Real" to a surprisingly tender take on Madonna's "Borderline" with singer Amanda Shires. A mostly acoustic rootsy feel ties the whole affair together as Emmanuel offers himself up as co-vocalist to Mark Knopfler on the backporch blues of "You Don't Want to Get You One of Those" and to Jason Isbell on Doc Watson's "Deep River Blues." As relaxed and affable as these vocal duets are, it's still the fireworks that get the biggest response and Emmanuel is smart enough to toss a pair of red-hot instrumentals near the front in the J.D. Simo and Charlie Cushman standout "Wheelin' and Dealin'" and the David Grisman and Bryan Sutton bluegrass blazer "C-jam Blues."