Reporter she was a gorgeous girl. A model who became a mom. You made good looking kids. Reporter on the eve of her sons fifth birthday she vanished. The whole time were trying to talk without the kids hearing us about what happened. Reporter when a woman disappears, police will have questions about a man in her life and in this case that would not be so simple. There was the estranged husband who admitted to an argument that wants landed him in jail. She came at me and i grabbed her by the arms and then she called the police. Reporter then there was the secret boyfriend, he was not telling all he knew. He was not upfront from the beginning. Reporter and there was a third man. The former colleague, with a crush. Cliff shared with friends that he found the love of his life. You have three potential suspects. A tangle. Reporter could investigators unravel it . We ask ourselves what does this mean . Reporter would her family ever find justice. Hello and welcome today on. They say good things come in small packages. Sandi johnsons family and friends would agree. The young mom was petite, pretty, and devoted to her two kids. But when she went missing police wondered if sandi some life was as happy as it seemed. The quickly uncovered a web of romantic relationships and a dark mystery that would take years to solve. Here is Andrea Canning with the disappearance of Sandi Johnson. Reporter it is a celebration the mother ever wants to miss. The childs fifth birthday. But suddenly she was gone. Out of his life. There is Nothing Anybody could really do to fix that repair the missing part. Reporter his mother, Sandi Johnson was outgoing. Energetic. And an awesome mom. Those kids were everything to her. Reporter why was she not there to sing happy birthday to her son . All they knew was that she disappeared into thin air. She should have seen you get married and go into the military and become a Police Officer one day. It is the toughest thing to deal with. Reporter it was heartbreaking and baffling. It was a true mystery as to what happened to sandi. Reporter structure mystery, what happened to the vibrant young mom who vanished from Seattle Suburb endured for years. Those who loved Sandi Johnson, those who long term, waited almost 2 decades for answers. And a slice of justice. The story starts in april, 1996. April 26th, to be precise. And friday. In the Seattle Area, the weather was doing what it does in this part of the world. Clouding up and spritzing rain. That day Sandi Johnson, a 28 yearold Wife And Mother have a day to do list as long as for arm. She was going to run into her errands that day to get ready for her Sons Birthday Party the next day. Reporter vicki was a good friend of sandis they bonded in the hospital after their sons both premature, were born on the same day. Sandi was a little younger than vicki , a tiny woman with a huge zest for life. I loved being around sandi. And it seemed like she really cared about people. Reporter No One knew that better than sandis cousins. Gina and nancy. They grew up together. Sandi is action, action, move, do. Talk it up and laugh always. She is a mile a minute. And beautiful. Gorgeous. Tiny. She were a 00. She modeled even. She did some modeling. I remember she did some kind of a bridal thing at one time. Reporter for friday, sandi took the day off from her job at a Car Dealership to prepare for the party. Sandis Husband Greg said she was always a mom first. Everything was about the kids, you know. Everything revolved around the kids. How excited was she to be a mom . I think she was really excited. I think that is what she wanted. She liked it. Reporter sandi had a plan. The kids would spend the day with vicki, while she zipped around town and that morning she left vicki a message on her phone. But 4 00 came and went and No Sandi. Vickis hands were full with her kids and sandis. At first, she was not too concerned. Maybe around 4 30 or 5 00 i started calling her because i thought you are not here yet and it was not like her and i was feeling frustrated. Reporter the hours went by and still, No Sandi. Vickis frustration turned to anger. But then she started to worry. Around 7 00 at night she began working the phones. We started calling greg and we started calling calling hospitals, the police. We were on the phone said we were worried. Reporter vicki and her husband kept Sandis Kids at their home that night. Did you sleep that night . Probably not much. I dont really remember. It is a fog. Unreal. What couldve happened to her . The next morning No Sandi. Had to get up and get ready to go to the Birthday Party. Just told sean it is okay, your mom will be there. Reporter meanwhile Greg Johnson was looking around his home. It was nothing to indicate that sandi had left in a hurry and somehow forgot to tell anyone. A strange is that would be. All her stuff was there. Called the police, called family , my sister, i think probably told her father. For you in a full on panic or are you like, maybe she ended up going out with friends. No. I was pretty worried. The circumstances at the house. I knew there was trouble. Or something not right. Reporter to the Birthday Party for sean went ahead on saturday. There was a cake and some presence. But No Sandi. The adults huddled and whispered the whole time we are all trying to talk without the kids hearing us about where is she and what happened. I think we made a second call to the Police Department in the afternoon. Did you think, weve got this Party And Sandi will show up for the party . That was our hope. We all tried to proceed as normal. Greg was crying like crazy. Good guess is on and he was trying to hide it. But there were tears. You remember anything about that day . Your fifth birthday . Unfortunately, i dont. You know. Reporter but Sean Johnson knows that the day his life changed forever. The day the apple questions started. Why is my mom not around and why this happened. Reporter they were very questions the police would start asking. Because thats a night they were called to is seattle supermarket. Store employees have noticed an abandoned vehicle in the Parking Lot. It was Sandi Johnsons car. Rookies were in it and so was her Cell Phone. But there was no sign of sandi. Coming up. That first break finding Sandis Car gives Police Hope but a second clue , will throw them for a loop. We are asking ourselves how does this come together and what does this mean . When dateline continues. A different condition called thyroid eye disease, which should be treated by a different doctor. See an expert. Find a ted Eye Specialist at isitted. Com nexium 24hr prevents Heartburn Acid before it begins. Get Allday And AllnightHeartburn Acid prevention with just one pill a day. Choose acid prevention. Choose nexium. Progress. Choose acid prevention. Moving in a positive direction. We all want our lives to do that. Why is progress also in our name . Weve always believed insurance should do more. Thats why weve gifted over A Thousand vehicles to veterans , funded Housing Programs for families in need and why were working to make roads safer. Youre doing good. And housing more fair. For us, thats real progress. Stay ahead of your moderatetosevere eczema. And show off clearer skin and less itch with dupixent, the 1 prescribed biologic by dermatologists and allergists, that helps heal your skin from within. Serious allergic reactions can occur that can be severe. Tell your doctor about new or worsening Eye Problems such as Eye Pain or vision changes including blurred vision, Joint Aches and pain, or a parasitic infection. Dont change or stop asthma medicines without talking to your doctor. Ask your Eczema Specialist about dupixent. [ ] your skin is everchanging, take care of it with gold bonds healing formulations of 7 moisturizers and 3 vitamins. For all your skins, gold bond. Protect against rsv with arexvy. Arexvy is a vaccine used to prevent lower Respiratory Disease from rsv in people 60 years and older. Arexvy does not protect everyone and is not for those with severe allergic reactions to its ingredients. Those with weakened Immune Systems may have a lower response to the vaccine. The most common Side Effects are injection site pain, fatigue, muscle pain, headache, and joint pain. Arexvy is Number One in Rsv Vaccine shots. Rsv . Make it arexvy. Choose advil liquigels for faster, stronger and longerlasting relief than tylenol rapid release gels. Because advil Targets Pain at the source of inflammation. So for faster pain relief, advil the pain away. Everybody wants super straight, super white teeth. They want that hollywood white smile. New sensodyne clinical white provides 2 shades whiter teeth and 24 7 sensitivity protection. I think its a great product. Its going to help a lot of patients. I think its a great prAndrea Canning hours after Sandi Johnson was reported missing, the police made a disturbing discovery. Sandis car, a Ford Escort Station wagon like this one, was found in the Parking Lot of a seattle Grocery Store. Hours after Sandi Johnson was reported missing, the police made it disturbing discovery. Sandis car in. A Ford Escort Station wagon like this one was found in the Parking Lot of the seattle Grocery Store. The doors were unlocked, the keys were in the ignition, sandi Cell Phone was lying on the seat. But sandi herself, was nowhere to be found. Cousins gina and nancy. When they found Sandis Car , did you go from thinking, she is missing and maybe will find her to she is gone. She is gone. I figured if someone had her, that is it. Reporter this was the detective for the King CountySheriffs Department in 1996. It must have been extremely alarming from the perspective of Law Enforcement when you find Sandis Car abandoned with the keys and her Cell Phone. Inside. At least it gave us an area to focus upon. The vehicle was located in southwestern King County. Reporter The Cops noted an unusual detail. The Drivers Seat was pushed back. Sandi, was tiny, cope with the seat in the forward position. Is close to the Steering Wheel as possible. Been just as they were processing the car, The Cops got another break. Sandis wallet was located lying in the Parking Lot at the hardware store. Oddly enough, it was miles from her car. They were puzzled. We ask ourselves how does this come together and what does this mean . What does it tell you when you find a car and a wallet and No Sandi . Sandi, clearly had been taken away from her vehicle in some manner. And at that point were very focused on why was this vehicle located here . Why was a wallet found across town . Reporter to detectives, it all added up to foul play. It was a very strange and compelling case. A mother of two small children, essentially just dropped off the radar screen. Was a baffling to the whole Police Department what happened to sandi . Yeah. Her disappearance became a priority with the Sheriffs Office right away. Reporter Sandi Spence Family put up flyers and joined the Search Parties in the greater Seattle Area, but there was one notable exception. Were you participating in the search . Not much. Reporter why not . I just cannot do that. Are pretty much stayed around the house with the kids and family. Today one question white is he not looking for . Never questioned me. Maybe amongst themselves, i dont know. Reporter but detectives are already taking a good, long look at Sandi Johnsons husband. Digging for details about the state of the couples marriage. The first thing you are doing is looking at those people that are closest to the person that is missing. You have to. So, it made perfect sense to focus on the husband early on. It always seems like the spouse. In this particular case we really did not know the dynamics of what had happened in their marriage. I mean, it is up to us to find out what are the details. Reporter they learn Sandi Met Greg and she pursued him and he fell fast. She had a lot of energy. A lot of. You see like you may be more lowkey. Was she a good complement to you . I think so. Reporter in late 1990, sandi got pregnant and the couple married. Sean was born in 1991. Daughter katie followed. For the next few years, the Couples Life was tech picked but happy. But in early 1996, four months before sandi disappeared , the marriage hit a rough patch. Greg moved out of the house and friends told the police there were Money Pressures among other things. What went wrong with the relationship . I think she said she could not talk to me or communicate with me. You know, we had seen a Marriage Counselor and working on some stuff. And i think it was getting better. You want to get back together. I was not against that at all. The maxwell Law Enforcement developed a very different portrait of the marriage and the chances for reconciliation. Listed Richardson And Carla, prosecuted the case for King County. They were talking about divorce and they had gotten to the point and it was assumed that they would be divorced. That was pretty reason for this it happened within the month before that that decision had been made. Reporter and investigators discover Something Else that troubled them. Law enforcement learned that they had argued only the day before she had gone missing. There had been a big Argument Witness by people at her place of work. So to focus some attention on her estranged husband. The argument was over money, which was a frequent point of dispute for them. She had trouble and he had trouble. Sort of meeting the bills. Reporter investigators questions were mounting and they had a couple with money problems, a troubled marriage, has been who did not search for his wife, and follow through the day before she disappeared. It was time to sit down with Greg Johnson. How did they treat you in that first encounter . The police . They were like, you know, you did it, you know. Accusing me of killing my wife. Told my sister that, you know, Greg Is did it. Reporter the usual suspect was starting to look like the right guy. It is getting bad and i am to the point that im afraid. When dateline continues. [narrator] life with Ear Ringing sounded like a constant Train Whistle i couldnt escape. Then i started taking lipo flavonoid. With 60 years of clinical experience, its the Number One doctor recommended brand for Ear Ringing. And now im finally free. Take back control with lipo flavonoid. Andrea canning Sandi Johnson was missing. Police believe she had been killed and they were zeroing in on her estranged Husband Greg. His world had turned upside down. Sandi johnson was missing. Police believe she had been killed and they were zeroing in on her estranged husband, greg. His world had