A County Durham man accused of killing his parents for a £230,000 inheritance has said he was on a drugs run for organised crime gangs on the day of their murders.
Stephen Seddon told a jury that he drove from his home in Seaham to Carrington, near Manchester, to deliver a holdall of drugs in return for cash.
The father-of-three maintained he returned straight home and did not visit parents Bob and Patricia on July 4 last year, the court heard.
Giving evidence, Seddon denied murdering or attempting to murder them and repeatedly said he would "never hurt them".
He said last summer's trip to the North West was to deliver the bag from an organised crime group in Darlington to a counterpart group in Manchester and it was the second such job he had done after a previous run on May 30.
Questioned by his barrister, Alan Hedworth QC, Seddon said: "I never looked in the carrier bag. It was quite obvious what it was...drugs.
"It was dropped at my house."
He met two people in Manchester on July 4 and picked up a bag of money in return which was later collected the same day from the back of his street, he said.
Mr Hedworth asked: "On that day did you go any further than that?
"No," replied Seddon.
"Did you have anything to do with the murder of your parents?" his barrister continued.
Seddon said: "Absolutely not."
The defendant said it never crossed his mind he would financially benefit from their deaths.
When arrested and interviewed under caution, the jury was told that Seddon chose not to answer "a lot of questions" and that he made no reference to the drugs run.
Seddon explained: "Operating in that league with those people, you don't mention names. It could get you killed."
Living with wife Nicola, in her home town of Seaham, he had a string of sales jobs in the motoring trade and CCTV security but had been unemployed since late 2011 and was financially dependent on his parents.
Asked about the alleged staged canal crash on March 20 last year, he said he had visited his parents to give a "belated Mother's Day present to my mother".
He said Mrs Seddon wanted to have a meal at a Beefeater restaurant at Altrincham Golf Course and he decided to take a short cut along Canal Road, Timperley.
Mr Hedworth asked him what he could recall of the journey.
He said he also remembered suffering a sharp chest pain and believing that he may have been suffering from a panic attack.
His dad screamed "we are in the water" and everyone in the car including his nephew, Daniel, "were going berserk", he said.
He could not get his seatbelt off and had to use a camping-style knife from the side compartment of his hired BMW car to cut it.
Seddon said he was the first out of the vehicle when he used a crook lock to smash open a window.
He helped free Mr Seddon and his nephew before firefighters arrived and rescued his mother.
Mr Hedworth asked him:
"The driving of that car into the canal...was that a deliberate act?
"No," the defendant said.
"Did you desire to kill your parents?" Mr Hedworth said.
"No, I would never hurt my parents.
Seddon, of Benavente Street, denies two counts of murder and two counts of attempted murder.