Re: Episode #504 'If Looks Could Kill' ***CONTAINS SPOILERS Rex Linn has been a regular for some time, but simply hasn't been in the credits. His character, Det. Frank Tripp, has been THE detective since Yelina left the show, and he is very much the analogue of Jim Brass on CSI: Miami. However, I don't care much for Natalia Boa Vista, and felt that she didn't need to become a regular, but some feel differently and I respect that. Overall, of the two, Rex Linn is a regular and should have been treated as such at least 2 seasons ago.