Are you a have-a-go hero?
Picture this: you're getting off the bus and a woman is lying on the ground in front of you with a teenager standing over her.
He's pulling at her handbag, breaks free and runs off.
Do you chase after him? Or do you walk on by?
Well, that's the decision 27-year-old Ifreanyi Obinwa had to make in Edgware one afternoon in August last year.
I'm sure many of us would have minded our own business. Ifreanyi didn't. He ran after the robber.
Unfortunately, he lost sight of him. He didn't give up. He asked a fellow Londoner who pointed in the direction of someone running.
Ifreanyi continued, finally catching up with the suspect in an alleyway. The man was emptying the contents of the bag.
Ifreanyi confronted him and they started to grapple on the ground. The suspect, however, escaped. Ifreanyi again sprinted after him and this time held him while calling the police.
But it didn't end there. A car pulled up and three men jumped out. They were the suspect's friends. Ifreanyi luckily wasn't hurt but the robber escaped.
When Met Police officers arrived, he took them back to the alleyway where key DNA evidence was found. It later led detectives to 19-year-old Michael Sarpong who had little choice but to plead guilty and was sentenced at Harrow Crown Court.
Now this is a strikingly similar story to one in East London.
You may remember Sukhwinder Singh. He chased after thieves who had snatched a woman's handbag in Barking in January. But tragically he was stabbed in the heart and died.
Clearly both men showed extraordinary bravery and courage. Some might describe their actions as foolhardy.
Others may say their selfless disregard for their own safety is the behaviour of heroes.
If you were in their position, what would you do?