narrator: joe gentz was now in custody. bob bashara, the man gentz claimed hired him to do the job, was not. you really believe that the husband's got his fingerprints on this thing. - yes. that he's the architect of the crime, right? yes, absolutely. narrator: so you're going to get to the husband via joe, i think, right? is that the strategy? at that point we believed joe that bob did this. narrator: bob bashara would have a lot to say about that. coming up, bob faces tough questions about his marriage. bob bashara: jane and i had a very good relationship. we had understandings on certain things. would you say it's what they used to call an open marriage in the '70s? it was a little bit like that, yeah. narrator: and jane's murder. did you murder your wife? did you cause her death? when "dateline" continues. on medicare? living with diabetes? progress is having your coffee like you like it. the freestyle libre 3 plus sensor is covered by medicare for more people managing diabetes with insulin. this is progress. ask your do

dennis murphy (voiceover): so detective narduzzi brought in this joe gentz. gentz, a massive man with a child's iq, denied having anything to do with the murder. but while the 48-year-old told detectives nothing, his body language said he had something to hide. mike narduzzi: he gets all flustered and loud and gregarious and he's upset. and he's kind of pacing around the interview room. and eventually he says he wants to leave. dennis murphy (voiceover): which he did. he was yet another strange and puzzling character who had entered the case, and narduzzi didn't know what to make of him. dennis murphy: how did this guy know bashara in the first place? they were introduced by steve tibaudo in approximately september of 2011. dennis murphy (voiceover): tibaudo owned an appliance and furniture store. steve tibaudo: bob stumbled into my place one day, probably 10 years prior to 2011. dennis murphy (voiceover): over the years, bashara bought appliances from tibaudo for his rental properties. joe gentz had worked for tibaudo in the past. joe's got a good heart. he'