and as for the susan berman case, attorney dick deguerin insists bob had nothing to do with her murderhen deguerin does go to court he faces a tough deputy d.a. named john lewin. >> you know, in texas we have a saying -- "ain't been a horse can't be rode, ain't been a cowboy can't be throwed." >> reporter: but will the upcoming trials solve the mysteries of robert durst? well, maybe not. which is why we're about to return to california and that place they call the lost coast. >> coming up. >> we drove from southern california up here. >> a missing teenager. >> i remember hanging flyers at the rest stops of my daughter, and just being like, "this is not happening right now. how could this be? karen, where are you?" >> investigators wonder is there a link? >> robert durst is a person of interest in this case. he is in the mix. >> when "dateline" continues. feel the clarity of non-drowsy children's claritin allergy relief. the #1 pediatrician recommended non-drowsy brand. because to a kid a grassy hill is irresistible. children's claritin. feel the clarity and live claritin clear. they wa