22 Seconds (A Women's Murder Club Thriller) by James Patterson

 In this thriller from a #1 New York Times bestselling author, SFPD Sergeant Lindsay Boxer has guns on her mind and only twenty-two seconds until she loses her badge—or her life.

SFPD Sergeant Lindsay Boxer has guns on her mind.

 There’s buzz of a last-ditch shipment of drugs and weapons crossing the Mexican border ahead of new restrictive gun laws. Before Lindsay can act, her top informant tips her to a case that hits disturbingly close to home.
 
 Former cops. Professional hits. All with the same warning scrawled on their bodies:
 
 You talk, you die.
 
 Now it’s Lindsay’s turn to choose.