When Anne Stevenson Smith started playing ukulele six years ago, the first song she learned was "Tonight You Belong to Me" because "it's the song Steve Martin sang to Bernadette Peters in The Jerk and it was already in my head," she said.

Her second song was the Rolling Stones' "You Can't Always Get What You Want" because "it's only two and a half chords over and over again, and it was already in my head," she said.

On Sunday afternoon, Smith, of Lower Gwynedd, and fellow-ukester Betsy Manning, of Pottstown, led a dozen strummers from their Philadelphia Main Line Ukulele Group through a two-hour meet-up jam of Halloween songs already in their heads at the Green Fork restaurant in North Wales.

Linda Tschoepe, who lives in town and baked the blueberry/pear and Jack Daniel's chocolate pecan pies for sale at the Green Fork's glass-enclosed counter, said, "You can't be in a bad mood when you play a ukulele."

Smith said that instant mood elevation explains why the group has grown from four ukesters sitting around a table at founder Foley Friedman's Wayne house six years ago to its current 420 members.

Mal Whyte, a British actor who spent 30 years in Irish theater before moving here and settling in Phoenixville, personified ukulele joy when he bounded up to the stage and did a pitch-perfect, scary-voice solo on "Monster Mash" – "The ghouls all came from their humble abodes to get a jolt from my electrodes" - while Smith and Manning sang the "ah-woo"s.

Whyte, who is left handed, played his right-handed ukulele upside down. "I bought it two years ago to share with my right-handed wife, hoping to get her interested," he said, laughing. "Did she get interested? No. So I have to play it upside down like Jimi Hendrix played guitar."

Late in the afternoon, Smith and Manning coaxed Whyte into employing his booming British baritone to narrate "Time Warp" from The Rocky Horror Picture Show - "It's astounding. Time is fleeting. Madness takes its toll ..." – while the group strummed along and smiled.

"The ukulele is a social and sociable instrument," Whyte said afterward. "So you play the ukulele?" serves as a conversational icebreaker, he said, "just before people ask you, 'So what did your grandmother do for a living?' or, as we say in Ireland, 'Who do you belong to now?' " he said.

Manning, who wore a black spiderweb shirt in honor of the Halloween meet-up, said she first learned to play as a child "on a really bad plastic ukulele that didn't hold a tune. [TV's irrepressible ukester] Arthur Godfrey was my first teacher, in a manner of speaking, although I never actually met him."

Perhaps scarred by the experience, Manning didn't take up the instrument again until a couple of years ago when Alvin "Pops" Okami, who handcrafts high end KoAloha ukuleles in Hawaii out of native woods, gave her one as a thank you for teaching a group of teenagers in Blackwood, N.J., to play his loving ode to this country, "America's Song."

A tiny fabric hula dancer dangled from one of Manning's tuning keys, swaying as Manning strummed and sung the haunting leads on "I Put A Spell on You" and Radiohead's "Creep" in her lyrical soprano voice.

When she's not writing grants for nonprofit human services organizations, Smith, who runs her Open Carry Ukulele page on Facebook featuring a photo of her walking down the street with a uke strapped rifle-style to each shoulder, said she's "all about the music all the time," shuttling between uke meet-ups at members' houses including her own and local coffee houses like Steel City in Phoenixville.

Often seen wearing her "Never underestimate the power of a woman with a ukulele" sweatshirt, Smith said the uke is "the hottest instrument on the planet" because it's small, only has four strings, offers beginners two-chord songs like "Don't Worry Be Happy" and, "If you know the C, F and G chords, man, you can play most of the rock songs on the planet."