LAURENCE Fishburne’s debut on “CSI” was a resounding success.

Fishburne, introduced on Thursday night’s episode, helped “CSI” snare nearly 21 million viewers, its best showing since its Oct. 9 season premiere.

“CSI” also notched season-best numbers in households with adults aged 25-54 and 18-49.

Fishburne, who plays criminal science professor Dr. Raymond Langston, is replacing “CSI” star William Petersen (Gil Grissom).