The Fox News Channel brought in a big name from a rival Thursday when it announced that it had signed Glenn Beck, the host of a widely viewed talk show on Headline News, a sister network of CNN.

Mr. Beck, who has frequently raised hackles in liberal circles with his acerbic conservative commentary, will host a new talk hour on Fox News from 5 to 6 p.m. weeknights. The show will not start until the spring, and a CNN press officer would not say when Mr. Beck would conclude his shows there. His contract ends in February.

Mr. Beck has been increasingly successful at Headline News, as his audience has more than doubled in the last year for the two editions of his hourlong weeknight program.

Mr. Beck appears first at 7 p.m. and then in a repeat at 9 p.m. The 7 p.m. show has been averaging about 375,000 viewers in recent months, and the 9 p.m. repeat exceeds 485,000 viewers.