Caiaphas was the high priest of Jerusalem at the time of Jesus, whose archenemy he is. He saw Jesus as a threat, and as a fraud, thinking that his miracles were only pretend, that those he was healing were pretending to be sick or hurt, and that those he was resurrecting were playing dead. He was assisted by his father-in-law, Annas. Caiphas' real name is Joseph, son of Caiaphas, but he is referred to by his father's name.
It was him who encouraged the Sanhedrin to stone St. Stephen, and who gave Saul authority to arrest Christians, and then go to Damascus to bring other Christians back to Jerusalem for destruction, the former of which he actually succeeds in, but during the latter, he is stopped and redeemed (Saul, that is), much to Caiaphas' dismay.
He is depicted as one of the main antagonists of Andrew Lloyd Webber and Tim Rice's musical Jesus Christ Superstar (Annas being the other). He is a bass. Like he did for real, he sees Jesus as a threat. He is played by Bob Bingham in the 1973 film and Frederick B. Owens in the 2000 Gale Edwards video. In the 2004 drama film The Passion of the Christ, his role is similar to what he did for real and was one of the main antagonists.