Pop shows: Nickel Creek, Thorazine, and the South Street Spring Festival

Nickel Creek went on hiatus after 2005's Why Should the Fire Die?, but the trio have reconvened to commemorate their 25th anniversary with a new album, the excellent A Dotted Line, and a tour that comes Friday to the Tower Theater. The band released only three albums between 2000 and 2005, but they got together as kids in 1989. Guitarist Sean Watkins was 12; his little sister Sara, on fiddle, was 8; as was mandolin player Chris Thile. They grew up playing and singing bluegrass, but they are by no means traditionalists, and part of the joy of their work is their genre-crossing unpredictability, from the electro-leaning cover of Mother Mother's "Haywire" to the fleet-fingered instrumental showcase "Elephant in the Corn" to the gospel harmonies of "21st of May." Joining Nickel Creek at the Tower: the Secret Sisters, with their own wide-ranging mix of rootsy harmony singing. - Steve Klinge

Reunited 1990s Philadelphia punk-rock band Thorazine tops a five-act bill Saturday night at the Fire. In 1995, the band, fronted by Jo-Ann Rogan, got a boatload of free publicity when SmithKline Beecham - now GlaxoSmithKline - sued it for naming itself (previously called Afterbirth) after a psychotropic drug. The suit was eventually dropped, and the band went on to record two albums for Hell Yeah records. Documentarian Heather Gillespie prodded the original members of the band to get back together, and they'll play this weekend along with beloved hard-core Philly band Pagan Babies and three other acts in a showcase sponsored by Philadelphia Brewing Co. - Dan DeLuca

On Saturday, there's much to do on South Street. It would certainly be enough if you focused on the German Maifest along the 700 block of South, with German beers and food (courtesy of Brauhaus Schmitz). But the South Street Headhouse District also has supersized its annual Spring Fest, closing South Street (between Front and Eighth), and the Second Street Plaza (between South and Lombard) for an expanded array of food vendors (restaurants such as the tony Serpico, and food trucks), artisan stands, and games for kids. The festival also has expanded its musical palette, from one stage to three, booked by the bosses of the blues-and-folk-centric Twisted Tail and the funk/rock-focused Legendary Dobbs. The Seventh Street stage will focus on German music (oompah rather than, say, Can or Kraftwerk), and the Fifth Street and Second Street stages will touch on everything from John the Conqueror's Mississippi-tinged blues to Cold Roses' alt-rock to Rowboat Casino's rap-rock. Don't miss the rockabilly of April Mae and the June Bugs at 11 a.m. and (about 4 p.m.) Johnny Popcorn, the jiving soul-funk ensemble founded by legendary local player/producers Tone Whitfield and Hezekiah. Every venue on South Street will offer musical treats, so make sure to stick your head in as many juke joints as possible. The Street will be showing its best. - A.D. Amorosi