It happened at 6:30 a.m. Monday at the north end of Boat House Row.
John Hewson of Center City was in a two-man boat when, he says, his partner had a seizure.
"The boat tipped. We went into the water," Hewson said.
Police were called to the scene as Hewson scrambled to keep his 6'4 rowing partner upright and breathing.
That's when an unknown jogger jumped in.
"I did not get his name. He jumped in over the rocks, banged up his leg pretty good, and helped pull us out," Hewson said.
Hewson's friend Jeremy was conscious and talking as EMS crews transported him to Hahnemann Hospital.
As for the Good Samaritan, he showered and jogged off. While he remained somewhat of a mystery, he did tell Hewson a few facts about himself: he was an architect who had attended Hewson's alma mater of Purdue University.
"Purdue engineer, architect in the city, and he just went away. He's a real hero," Hewson said.
But the mystery did not last long. After some social messaging, jogger Stephen Giorgio revealed to Action News that he was the one who jumped into the river.
He said he first spotted Hewson holding onto an overturned boat.
"He has a guy on the shoulder and his lips are turning blue," Giorgio said.
Ditching his shoes, Giorgio jumped in.
"The guy said his foot was caught in the straps of the scull. So I just went under and I undid his shoes," Giorgio said.
That allowed them to move to safety.
Giorgio rejects the hero title arguing Hewson did the extraordinary stuff.
"No, the guy, John, was holding was him up for a good ten minutes in the water by himself," Giorgio said.
Both Hewson and Giorgio did indeed go to Purdue University ? one was the class of 1997, the other class of 2004.
Meanwhile, Hewson's friend Jeremy remains hospitalized, but is expected to be okay.
Coincidentally, while he did not go to Purdue, Jeremy, too, is an architect.