Pensioner Stephen Breed was on the London underground, when he saw a young woman being abused by an aggressive thug over her "noisy" phone.
Concerned for Polly Collins, he immediately stepped in to defuse the situation.
We're sure Polly, 43, was really grateful - but little did she know, she'd get to repay the favour just moments later!
Because when the 65-year-old stepped off the tube, he suffered a massive heart attack and collapsed to the floor.
Luckily Polly, a nurse, saw him and immediately rushed into action, performing life-saving CPR on the man who had just stepped in to save her.
And it was fortunate she was there, because paramedics confirmed that Stephen had technically died three times.
Stephen was quoted in The Sun, saying: "The guy had a go at Polly. He was awful, so rude. When he confronted me, my heart was racing. Seconds after I left the train, that was it. Goodnight Vienna."
Polly was also quoted, saying: "He defended me and it turns out he was the one who needed defending. If he'd died I would've had to live with it for the rest of my life. He didn't need to do what he did."
Thank goodness they were there for each other!
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