S. Prt. 107-84 -- Executive Sessions of the Senate Permanent Subcommittee on Investigations of the Committee on Government Operations (McCarthy Hearings 1953-54). Closed according to Senate rules for 50 years, these hearings are now available to researchers and the public.
This five-volume collection of Senate hearings is available online (in PDF format). Volumes 1-4 cover the 1953 hearings, and 1954 hearings are found in volume 5.