The caller is Rose Larkin (Luciane Buchanan), a tech whiz living with her aunt and uncle, who, unbeknownst to her, were undercover agents under the U.S. government's secret Night Action program.

Season two, which premieres Thursday, follows Peter's role as a night agent. After Peter is tasked with tracking down a CIA agent accused of leaking secrets, he and Rose Larkin (Luciane Buchanan), the ...