CHICAGO (AP) — Mandolin player and composer Chris Thile learned the hard way that when you get a call from the 312 area code this time of year, you should probably answer the phone.

Thile is among 23 recipients of this year’s MacArthur Foundation “genius grants,” which are given in a secrecy-shrouded process. Winners have no idea they’ve been nominated for the $500,000 awards until they get the call, and nominators must remain anonymous.