On ‘Mercury — Act 2,’ Imagine Dragons offer a light at the end of the tunnel

Imagine Dragons ,with lead singer Dan Reynolds, perform on stage on the third day of the Pinkpop music festival in Landgraaf, The Netherlands, on June 19. (Getty)

“Mercury — Act 2,” Imagine Dragons (Interscope)

If you were hiding under your bed after listening to the last album by Imagine Dragons, it’s time to come out. The second volume of “Mercury” is upbeat, often Caribbean-spiced and throbbing. It’s the sound of a band getting its arena groove back.