New Line is going to prison, buying action spec “Warden” from siblings John and Thomas Sonntag, and setting it up with Mosaic to produce.Jimmy Miller and Lawrence Inglee are producing. John Zaozirny and Bobby Sabelhaus will exec produce. Story centers on a prison warden who — when his wife and son are kidnapped — is blackmailed into helping the American head of a Mexican drug cartel escape from his own high-security facility. New Line’s Michael Disco and Sam Brown are overseeing “Warden.” Earlier this year, Voltage Pictures sci-fi spec “Alter” from the Sonntags and set it up with Benderspink and Stephen L’Heureux. The Sonntags are repped by UTA and Mosaic.