A woman whose car plunged into a river was saved from "certain drowning" by a man who dived into the water after hearing her screams.
Stephen Jones heard the crash from his parents' home near Wisbech, Cambridgeshire, on Sunday night.
He jumped into the 12ft (3.6m) deep North Level Drain as her car sank and pulled the driver free in pitch black darkness.
The 34-year-old said his heroics were "what anyone would do".
The woman was unhurt but later charged with drink-driving.
Mr Jones, from Woking, Surrey, was visiting his parents in Parson Drove when they heard "an almighty sound" at about 21:15 BST.
The car had careered through metal railings and plunged into the middle of the water where it started sinking, he said.
"I think the the scary bit was the fact you could hear the person inside the car screaming for help, which was terrifying.
"I went straight into the water and tried to open the doors first of all, but couldn't.
"Luckily the windows were already smashed, so I went underwater and unlocked the doors and just had a feel around.
"I managed to feel someone in there and pulled them out."
Mr Jones said he was in the "freezing, pitch black water" for about four minutes trying to free the woman.
Police, the fire service, an ambulance and air ambulance were all called to the scene and were "amazing", he added.
Mr Jones was later praised by police on Twitter, who wrote: "Steve, thank you for your life-saving actions."
"It could have been an awful lot worse than it was. I just did what any human would have done if you heard screams," Mr Jones said.
"The fire chief told me [the woman] would certainly have drowned if I hadn't gone in to help."
The woman, 58, from Spalding in Lincolnshire, will appear before Peterborough magistrates on 17 May.