Diners watched in disbelief as restaurant staff dressed as the Power Rangers lept to the defence of a woman who was being choked.
The real-life action heroes saved the day in battling off the lady's attacker.
One of the shocked witnesses, Ploi Pirapoken, sat down to enjoy a dinner out at Noka Ramen in Oakland, California when the event unfolded.
Recounting the bizarre incident on Twitter, she wrote: "The craziest thing just happened at dinner. I’m at a ramen shop owned by Thai people in Oakland dressed as power rangers when a woman comes rushing in saying she wasn’t safe—and a man came running in after her and puts her in a chokehold.
She continued: "Once the woman had expressed she wasn’t safe, and she didn’t want to go home with this man who was choke holding her, the black power ranger (the manager with a kickass bob) and the yellow ranger, told the man to leave.
"He swung at them. This is when all rangers yelled, “Huey!”
'Huey' is a Thai expression of disbelief, comparable to 'What the f***?' in English, explained Ms Pirapoken.
Staff had dressed as power rangers in support of the main Noka te cocktail they sell - The Noka Rangers.
Ms Pirapoken explained how the man started yelling racial slurs and tried to push through to the kitchen.
The 'Yellow Ranger' then grabbed him by the collar and dragged him out of the restaurant while the man threw punches and kicks.
There was chaos in the restaurant, Ms Pirapoken said: "We’re trying to call the cops. Patrons are shaking and crying. The pink power ranger [hostess] tells us our food is free."
The man then went outside and started throwing things at the restaurant window.
Police had been called but before they turned up, the man and a friend tried to force their way back into the restaurant.
The Power Rangers lept back into action, piling in to lock them out and protect the patrons inside.
Oakland police have confirmed they detained a man who was going through a mental health crisis. He has been taken for medical care.
The restaurant wrote in a statement on Instagram : "Like our heroic namesakes, it’s not just the powers and costumes that give us strength. It’s who and what we are inside that empowers us,"
"While we’re proud of our team for going above and beyond in our time of need, we would like to assure our guests that this event is an anomaly at our restaurant.
"The safety of our guests and employees is of utmost importance to us. We are fully cooperating with the police in identifying the individual involved."