A few decades ago, a group of history sleuths started piecing together the long-lost tale of America’s worst maritime disaster. On April 27, 1865, the Sultana steamboat carrying an estimated 2400 passengers—mostly former Union prisoners of war—blew up and sank in the Mississippi River just north of Memphis. The event received scant national attention, and no exhaustive, historical research was done on the topic until a Memphis lawyer took up the task in the late 1970s. 

In time, books emerged, along with a Sultana descendants association and a Clive Cussler expedition to the final resting place of the vessel which had been grossly overloaded with more than six times its listed carrying capacity. And in recent years, interest in this paddlewheel boat whose three boilers exploded that fateful night, killing 1800 people, has only grown. There’s now a Sultana museum, and the boat has been featured in two television specials, a 90-minute documentary film, and even an anniversary burger.

With the build up to the sesquicentennial, Americans have never been exposed to more Sultana minutiae of every stripe and color. Teams of archaeologists, historians, genealogists, collectors, and scuba divers have solved every mystery involving the Civil War’s last great human tragedy.

Well, almost every one: This story’s Public Enemy No. 1 still lurks in the shadows. Experts know who he is, but they don’t know what he looked like. While photos have been found for every other major Sultana character, images of Col. Reuben Hatch remain missing.

“He is perhaps the most culpable person responsible for the overcrowding of the Sultana. Yet he remains, in death, as shrouded in mystery as he was while living,” Mike Marshall, producer of the newly released Remember the Sultana film, tells mental_floss. “Hatch seemed determined to be elusive as possible throughout his life. To that end, his success has to date been complete.”

In April 1865, Hatch worked as a chief quartermaster in Vicksburg. Thousands of Union POWs had recently been freed from prison camps, and Hatch’s job was to take care of them before they headed back to their homes in northern states. There was big money to be made by the steamboat lines tasked with this job, and many experts agree the Sultana’s captain successfully bribed Hatch to get an outsized cut of it. "On a scale of one to 10, 10 being the most corrupt, Reuben Hatch would be a 12,” lawyer Jerry Potter, author of The Sultana Tragedy, told the Daily Beast.

Evidence had started pouring in years before, when Hatch was an assistant quartermaster in his home state of Illinois. Reportedly, he indulged in graft there, involving government lumber purchases, the selling of army supplies, and steamboat charter fraud. According to The Sultana Tragedy, as investigations began, Hatch apparently tried to destroy the evidence by dumping it into the Ohio River. But the doctored ledgers washed ashore and were found shortly thereafter.

In this situation, most other officials would be toast. And indeed, it appeared a court-martial for Hatch was imminent. But he had very powerful connections to save him. His brother Ozias Hatch, for starters, was Illinois’ secretary of state and one of Abraham Lincoln’s closest friends and political campaign benefactors.

Ozias Hatch asked Lincoln to vouch for his brother’s character to a judge advocate general, and he did. Lincoln also recommended a few people for the three-person commission that would decide Reuben Hatch’s fate. Ultimately, two Lincoln cronies were appointed and Hatch was cleared of all charges.

Mishaps mark the entirety of Hatch’s military career during the Civil War, yet improbably he kept getting promoted. Experts agree that as he ascended the ranks, he almost certainly would have had his photo taken. Not only did his powerful brother and contacts help shield him from “from his own ineptitude and ethical lapses,” Marshall says, but it’s possible he might have received help in his later years covering his own material tracks.

Hatch was relieved of his duties in June 1865 and lived in the Pittsfield, Ill. area before dying six years later at age 53. He was never charged with any crimes involving the Sultana. Indeed, nobody was ultimately held responsible for the death of an estimated 1800 Americans.

One of those casualties was Pvt. Adam Schneider, whose descendant Pam Newhouse has made it a mission to find a photo of Hatch. Despite trips to all manner of libraries and archives, small-time, national and everything in between, she’s had no luck so far. The same rings true for Potter—who has been looking for a photo throughout his 37 years of Sultana research—and Marshall, who’s tried to find leads on Ancestry.com. For his movie he ended up commissioning an artist to sketch an image of Reuben Hatch from behind.

At this point, the group’s options are limited. They hope to visit the county historical society near Pittsfield, Ill. and examine documents there. Another potential lead: a grainy 1865 photo taken at the Mississippi parole camp near Vicksburg. Marshall says Gene Salecker, author of Disaster on the Mississippi and the owner of a vast cache of Sultana-related relics, believes one of the dozen men depicted may be Hatch.

Apparently, notes exist on the back of the photo which identify all the officials by name. But the Dallas auction house that owned the photo didn’t make a scan or record of those names before selling it a few years ago, Marshall says. “To complicate things, the purchaser of the photo refuses to let anyone see it” and won’t allow release of his contact info.

The Hatch searchers are cautiously optimistic their mission will one day hit paydirt. They can take heart that another end-of-the-Civil-War mystery—the exact color of Abraham Lincoln's funeral train car—was recently solved after many decades of research. In that case, an artifact owner was also reticent but eventually thawed; the breakthrough came when he allowed researchers to study a piece of the train’s window trim.

Pam Newhouse hopes a similar windfall awaits her group. “In the big scheme of things, it’s only a picture,” she says. “But we’d really like to find it. All these small details add up to paint a full picture.”