 The VCTF is called in to investigate the seemingly random murders of four people beaten to death during a rainstorm. Sam and the team consults with a psychologist who informs them of a syndrome where people become extremely violent in response to certain types of weather. The clues lead to a construction worker afflicted with the seasonal disorder. Meanwhile, Sharon Lesher, a young felon is released from prison and is met by her pen pal, Jack, whom he takes back to his lair and it becomes clear this is the beginning of an "unholy alliance." Also, Bailey laments the fact that the police plan to charge Frances with attempted murder once they determine her whereabouts.