The phrase "puts on the rack" refers to the act of subjecting someone to intense physical or mental pressure in order to extract information or elicit a certain response. Synonyms for this phrase include "puts through the wringer," "grills," "interrogates," "cross-examines," "presses," and "examines thoroughly." Each of these phrases conveys the idea of subjecting someone to intense scrutiny or pressure in order to uncover the truth or elicit a certain response. While these phrases are often used in the context of police or military interrogations, they can also be used in everyday situations where someone is being put under a lot of pressure or scrutiny.