(This story was first published on March 5, 2005.) 

How can two people simply vanish off the face of the earth?

How is it possible that a couple in their 30s can leave a bar on South Street one night, and then just disappear? 
For the last two weeks, the families and friends of Danielle Imbo and Rich Petrone have been struggling desperately to answer those questions. 
But there are no answers. Just a mystery that is unbearable and unending. 
"You feel like you're trapped," says Petrone's father, Richard. "Each day is the same. It's like you're in this awful dream, and you're caught in quicksand."
"Your emotions run wild," says John Ottobre, Imbo's brother. "You could sit there and speculate until you're blue in the face and make yourself crazy. But we don't have a lead, in either family."
As much as the families would hope it might be the case, they say there's no way the couple would have simply run off. 
Both Imbo and Petrone, who had been dating for nearly a year, have stable, ordered lives, and children from previous relationships who, family members say, they would not have abandoned. 
Imbo, 34, works for a mortgage company out of her home in Mount Laurel, N.J., so she can take care of her 2-year-old son. 
Petrone, who's 35, works side-by-side with his father every day at the family bakery in Ardmore and recently moved to South Philadelphia to be near his 14-year-old daughter. 
Ominously, the couple's cell phones have not been used in the last two weeks, and there has been no activity on their credit cards or in their bank accounts, the families say.
So what happened to the couple after they walked out of Abilene's bar and restaurant about 11:45 p.m. on Saturday, Feb. 19? 
Police in Philadelphia and New Jersey - where the couple were apparently headed - have launched an intense investigation, checking financial records, interviewing family, friends and neighbors, even searching the banks of the Delaware River by helicopter. 
"We haven't found anything to indicate foul play, but all of our options remain open," said Capt. Joseph O'Brien of the Philadelphia Police South Detective Division. "We have several areas that we're pursuing. But we're not close to reaching any conclusions."
Says Petrone: "I think basically the police are at square one."
Anthony Valentino and his wife, Michelle McLaughlin, were the last people known to have seen Imbo and Petrone. They were all at Abilene's, on South Street near 5th, having a couple of drinks and listening to a band. 
"It was a normal kind of night," says Valentino, who has been friends with Petrone since they were 10-year-olds on a South Jersey hockey team. "We were sitting by the bar, and when they left we just hugged and said goodbye. That was the last time I saw them."
Petrone's father says the couple had planned to spend the night at Imbo's house in New Jersey.
No one knows whether they made it there. There has been no sign at all of the couple or of Petrone's pickup truck. 
"We don't understand how this could happen on South Street, where there are hundreds of people and no one saw anything," Petrone said. "And they were driving all the way on highways, main roads. Where did they go?"
It wasn't until the next day that the families realized the couple were missing. Rich Petrone had planned to come back to his apartment on Snyder Avenue near 16th Street on Feb. 20 to watch the Daytona 500. 
Imbo had an appointment at 11 Sunday morning at a Cherry Hill hair salon, Petrone said. She had planned to return home after that to do mortgage work. 
Her 2-year-old son, Joseph Imbo III, had spent the night with her estranged husband, and they had arranged for the child to be returned home about 3:30 p.m.
Petrone's sister, Christine, is a longtime friend of Imbo, and works at the hair salon where Imbo was expected. But when Imbo didn't show up, and didn't answer her cell phone, Christine grew worried. 
Meanwhile, Petrone's mother, Marge, had been trying to call her son. He wasn't picking up the phone at home or answering his cell phone, which had been turned off. 
"That was odd, because he almost never shuts his phone off," says Petrone. About that time, Christine called to tell them she couldn't reach Imbo. 
"That's when we really started to get concerned," said Petrone.
Although Imbo and Petrone had not dated long, they'd known each other since they were 15. 
Imbo went to Cherry Hill High School East, and Rich and Christine Petrone went to Bishop Eustice Prep, but the two girls knew each other and were close friends. And Danielle got to know Rich Petrone as well. 
"Danielle was always crazy about Rich in high school, but he was into hockey," Petrone's mother recalled. Years later, he said, "I didn't even know she liked me."
After high school, Imbo had several jobs before going to work for a mortgage company, her brother said. 
She got married about three years ago, and until she became pregnant, was the lead singer in a pop-rock band, the Schoolboys, which played at local bars. 
She was, her brother says, following in the footsteps of their father, John Ottobre - known throughout Philly and beyond as do-wop singer "Johnny October." Ottobre led the Philadelphia-based group the Four Dates, which gained national popularity in the 1950s. 
Petrone had worked at his parents' Ardmore bakery, Viking Pastries, since he was young and after high school, decided to join the family business. He went to the Restaurant School and became a master at making wedding cakes. His speciality is a shaved-chocolate cake, says his mother. 
He had a daughter, Angela. He and her mother never married, and when Angela was 3, she came to live with Petrone in the apartment over the family bakery. He raised her by himself, until about a year ago, when she went back to live with her mother. 
It was around that time that Imbo and Petrone began dating. 
"They met up again and they clicked," Petrone's mother said. "They were happy."
For the past two weeks, members of the two families and dozens of friends have done everything they can think of. They've scoured the South Street area again and again for Petrone's truck. They've put up posters in stores, pizza parlors and motels from Philadelphia to the Jersey shore. 
They've handed out fliers to people leaving events at the Wachovia Center, they've searched garages at the trains station and airport - on foot - for any sign of the truck. 
Through it all, the families have had to find some way to make it through the day. 
Marge Petrone says it's very hard for 14-year-old Angela. 
"I don't think it's real for her, but then she'll see a poster someplace. It's horrible."
And she said her husband is having a difficult time as well. 
"Just the other day he said, 'I may have to sell the bakery. I don't know how I can do it without him there.'"
Says Richard Petrone: "Every day I wake up and I hope the phone's going to ring and Rich is going to say, 'Dad, you won't believe what happened and what we did.' But if you're realistic, you know in your gut that something is wrong. You don't ever want to rule out hope, but it's not a bright and sunny outlook."
Marge Petrone says she holds her son's Bobby Clarke hockey jersey and thinks of him. 
"I still feel him," she says. "That's how I get through the day."