By James Hibberd
April 28, 2011 at 06:23 PM EDT

UPDATED: The creator of the most-watched drama on TV is suing CBS for making a successful spin-off of his hit series.

JAG and NCIS executive producer Don Bellisario filed a breach-of-contract lawsuit Thursday against producer CBS TV Studios for making NCIS: Los Angeles, which airs back-to-back with NCIS on Tuesday nights. 

According to a lawsuit filed in Los Angeles Superior Court, Bellisario left NCIS in 2007 and was not compensated for the spin-off, which CBS launched in 2009. The creator argues he has the right of “first opportunity to participate creatively and economically in the development of such programs.” Moreover, that by creating JAG and NCIS, he also essentially created NCIS: LA — “the show scrupulously replicates that which has made NCIS so popular and it does so with near clone-like fidelity to Bellisario’s recipe,” and the programs share some of the same characters.

CBS, contends Bellisario, was contractually obligated to either let him write and produce the spin-off, or pay him off. No exact damages were requested, but there’s plenty of money at stake here, given the success of NCIS: LA, which has already been sold into syndication for an estimated $2.3 million per episode.”

UPDATE: CBS TV Studios responds: “Don Bellisario has no rights to what he is claiming in this suit. The contract is clear, the facts are undeniable and the courts won’t need Naval intelligence to conclude that the case has no merit. We continue to honor all of our obligations to Mr. Bellisario under the actual agreement.”