The Big T.N.T. Show is a 1966 concert film. Directed by Larry Peerce and distributed by American International Pictures, it includes performances by numerous popular rock and roll and R&B musicians from the United States and the United Kingdom.

A sequel to 1964's The T.A.M.I. Show, and, like it, executive produced by Henry G. Saperstein, The Big T.N.T. Show was likewise shot on videotape and transferred to 35-millimeter film. Some footage from it was reused in the film That Was Rock a.k.a. The T.A.M.I. / T.N.T. Show (1984).The concert was shot before a live audience at the Moulin Rouge club at 6230 Sunset Boulevard Los Angeles, California on November 29, 1965. During the opening sequence of audience shots, Ron Mael and Russell Mael, who would later form the band Sparks can be seen at 4.44 and Sky Saxon, singer and frontman for The Seeds can be seen at 5.21. Frank Zappa appears very briefly in the movie (6.30) as an audience member and can also be seen in the movie's trailer. Marilyn McCoo of the Fifth Dimension also appears as one of the backing singers during Ray Charles' performance. Its pre-release title was This Could Be the Night. The film's theme song, "This Could Be the Night", was written by Harry Nilsson, produced by Phil Spector, and performed by the Modern Folk Quartet.