Police say the women were raped, the men robbed and the attackers even stole the clothes off their backs.
"It's horrifying," said Sgt. Charles Fitzgerald, Detroit police. "It's just awful."
Police believe six men are responsible for two robberies and rapes of two different couples Thursday night. Each happened hours apart on Detroit's west side.
The first couple in their early 20s, was walking near west McNichols around 10 p.m. say six men approached with a gun and forcing them into an alley.
"Both victims complied," Fitzgerald said. "They were forced to the ground, the male victim was forced to watch the 21-year-old female victim get sexually assaulted."
The six suspects then stole their cell phones and stripped them of their clothing.
An hour and 40 minutes later, police say a group of four men - approached another couple, a 19-year-old woman and 21-year-old man.
"Similar M.O. they approached them on foot, they were forced into an alley and the exact same thing occurred."
Police say the men could have been in a blue Ford sport utility vehicle as the two women got a clear description of one attacker in both assaults.
"It's a black male, 22 years old, five-foot-8, 150 pounds, goatee mustache, he was wearing a blue polo jogging suite with a red emblem," Fitzgerald said.
Note: His composite sketch can be seen on the far left photo. Two other suspect sketches (middle and right) were taken from the July 11 incident which matched the other two attacks.
Detroit police say this group of men may even be responsible for a third rape and robbery. Back on July 11, that incident involved three men with similar descriptions.
The other men in the most recent attacks are described as black men in their 20s, one about 5 foot-9, roughly 220 pounds wearing a gray hoodie.
Another is 6 feet tall, 150 pounds wearing a black and white Adidas shirt and matching shoes.
Detroit police, unsure of the original motive or if these crimes are gang-related, say although these couples were not alone. They remind everyone to be on alert..
"If something doesn't feel right, run to a store or a well-lit environment," Fitzgerald said. "Use your sixth sense."
Anyone with information should call Detroit police or Crime Stoppers at 1-800-SPEAK-UP.