In the “it had to happen” category comes Brooklyn’s Gangstagrass, a five-piece outfit that has created a new fusion of musical idioms – in this case, the marriage of traditional bluegrass and contemporary hip-hop. Led by songwriter, producer and guitarist Rench, the group has released an album that amounts to a personal manifesto in the form of the hilariously titled “Rappalachia.” The deeply American hybrid rather seamlessly brings together urban and rural worlds, as hip-hop beats are adorned with seriously virtuosic bluegrass pickin’. Viewers of the TV series “Justified” might already be familiar with Gangstagrass – the band’s “Long Hard Times To Come” is the show’s theme song.

Gangstagrass performs at 7 p.m. Monday in the Forvm at the Maple Entertainment Complex (4224 Maple Road, Amherst). Three Buffalo acts, representing rock, rap and underground hip-hop – Whiskey Reverb, AJ Jordan and Dan Martin – will handle the opening duties. Tickets are $10 in advance at the Forvm box office, or $12 on the day of the show.

– Jeff Miers