Lines and Shadows Mass Market Paperback – November 1, 1984 by Joseph Wambaugh 
 
Not since Joseph Wambaugh's best-selling  The Onion Field has there been a true  police story as fascinating, as totally gripping as  . . .Lines And Shadows. The  media hailed them as heroes. Others denounced them  as lawless renegades. A squad of tough cops  called the Border Crime Task Force. A commando team  sent to patrol the snake-infested no-man's-land  south of San Diego. Not to apprehend the thousands of  illegal aliens slipping into the U.S., but to stop  the ruthless bandits who preyed on them  nightly--relentlessly robbing, raping and murdering  defenseless men, women and children. The task force plan  was simple. They would disguise themselves as  illegal aliens. They would confront the murderous  shadows of the night. Yet each time they walked  into the violent blackness along the border, they  came closer to another boundary line--a fragile line  within each man. and crossing it meant destroying  their sanity and their lives.
 
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