Just when it seemed like Tom Petty and the Heartbreakers were taking 2015 off from live performances, they turned up for a surprise set at the Troubadour in Los Angeles on Dec. 19.

Petty's appearance -- which included Heartbreakers Mike Campbell, Benmont Tench, Ron Blair and Scott Thurston with Matt Laug sitting in on drums for an absent Steve Ferrone -- didn't arrive completely out of nowhere. That night, the club was playing host to the fourth annual Merry Minstrel Musical Circus, a "holiday gathering and jamathon" organized by Campbell and singer/songwriter Jonathan Wilson — and it wasn't the only set of the night, which also saw performances from Jackson Browne and Dawes.

Still, the Heartbreakers set offered an unexpected treat for guests who watched the band run through 10 songs — many of which you can watch courtesy of the fan-shot footage above and below — and included the bonus of a guest appearance from Jeff Lynne, who joined them for "Runaway," "Poor House" and "Roll Over Beethoven." The whole evening was arranged to benefit the Tazzy Animal Rescue Fund.

The Troubadour gig seems likely to be the last time we see Petty perform with the Heartbreakers in the immediate future. Earlier this year, he talked about plans for a new record with his earlier band, Mudcrutch, and although that group's lineup includes Campbell and Tench, it could be awhile before we get a follow-up to the most recent Heartbreakers effort, 2014's Hypnotic Eye.

Watch Tom Petty and the Heartbreakers at the Troubadour, Dec. 19, 2015

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