It's a must-see show for bluegrass fans tonight when The Grascals perform at the Arcata Theatre Lounge. For those unfamiliar, the Grascals are among the most beloved and acclaimed bands on today's bluegrass scene — they've won a slew of awards and been nominated for a number of Grammys, plus they've appeared on The Late, Late Show with Craig Ferguson, CBS's Early Show, Fox & Friends and The Tonight Show, and toured with both Dolly Parton and Hank Williams, Jr. Doors open at 8 p.m., cover is $18 at the door or $15 advance, and this show is 21-and-over.