How much is an episode of "Castle" worth? Apparently not as much as "Hawaii Five-0."

But no worries. Cable channel TNT wants them both.

TNT has picked up "Castle," starring Nathan Fillion and Stana Katic, for $1.5 million per episode. It plans to start airing the episodes both on its main channel and online as early as next summer, according to Broadcasting & Cable.

Michael Wright, the executive vice president of programming for TNT, TBS and Turner Classic Movies, called "Castle" a perfect complement to its growing list of original programs.

The deal won't affect "Castle's" life on ABC, where new episodes currently air, but will give old episodes a home that doesn't just have to include DVD.

It will join "Hawaii Five-0," the CBS reboot that premiered this past season to pretty decent ratings -- and a show that goes head-to-head with "Castle" on Mondays. Yet, CBS was able to get $2.5 million per episode out of TNT for "Hawaii Five-0."

"Castle," which will start its fourth season in the fall, averaged a 7.2 rating/12 share on Mondays, according to Fast National overnight ratings from The Nielsen Co. That was well ahead of the pace set by "Hawaii Five-0" against it, which managed a respectable 6.7/11 in its premiere season.

Yet, it was likely the "Hawaii Five-0" brand that helped boost its value, as well as its potential appeal to a slightly different -- and more affluent -- audience. That show is expected to start on TNT in 2014, joining another CBS program, "The Mentalist," which just debuted on TNT recently at $2.2 million per episode.

Lucrative post-run syndication deals like the ones for "Castle," "Hawaii Five-0" and "The Mentalist," can really help boost these show's chance for survival in the new episode realm on their respective networks. Knowing that millions of extra dollars can be generated guaranteed through a syndication deal, a production company may be more apt to reduce a licensing fee to keep a show on the air, or if a network owns the program, to keep it going to help future profits.

Both shows air Mondays at 10 p.m. ET. "Castle" is on ABC, while "Hawaii Five-0" is on CBS.