William Giraldo didn't respond to reporters' questions as he was led off to jail.
He had his head down, but police say the public has seen his face before.
Investigators say the 24-year-old was caught on camera at a Dunkin' Donuts.
It is surveillance video police released as they tried to solve three attempted sexual assaults and one rape.
They have now charged Giraldo with the June 4 rape of a woman in the vestibule of her apartment building in Sunset Park.
However, the arrest of the suspect only raises more questions and concerns because some can't help but wonder if another suspect is still out there.
When it comes to three other attempted rapes, including one caught on surveillance video in which the victim fought off her attacker, it is unclear if police consider Giraldo a prime suspect.
The Park Slope resident whose security camera captured that attack told me the suspect "does not look like him to me."
He got a look at him, he says, when he tried to help the victim.
"If they got the right guy, I'm pretty sure I will recognize him," he said.
The video does not offer a clear shot of the attacker's face.
"We all looked at the video, but really it's so grainy that all you can see is a big man," said Diana Adams, a self defense instructor who lives across the street from the attack.
Police did release a sketch of the man they think was responsible for all four attacks.
But when they released a photo of a suspect, William Giraldo was recognized by family members.
He came to police to clear his name, officials say, but the victim picked him out of a lineup.
Police officials also said the Internal Affairs Bureau is investigating why officers responding to the first attack did not tell detectives or department video experts to return and get the video.
The resident who claims he offered it to police that night told me they finally came back a month later. .