A widower who heard his wife's last moments before she was murdered on the phone will be pushed to the limit as he appears on Channel 4's SAS: Who Dares Win.

Dan Cross, 40, lost his wife Nikki Cross, 37, in September 2015 after she was killed in their family home while Dan listened on the phone.

The telecoms engineer was out on a business trip when he received the phone call from his wife.

She told him that there had been a strange man hanging around the house earlier in the evening. As Nikki was explaining to Dan that she had already called the police, she heard a crashing sound in the other room, which she then went to investigate.

Dan immediately called 999 on another line but was helpless as he was forced to listen to his wife plead for her life. The line with Nikki went silent and Dan knew that the worst had happened.

Since then he has had to come to terms with the loss of his wife and deal with post traumatic stress disorder (PTSD) and anxiety.

He has also had to bring up his children without his wife to help him.

Mr Cross has been appearing on the show since Sunday (January 14) as he is put to the test both mentally and physically in a series of challenges that are as close as civilians can get to special forces training.

Despite fearing that his age might make the physical side of the training a struggle, he is determined to test how tough he really is.

Dan has dedicated the last two years to looking after his children, making sure he is doing everything he possibly can to ease their suffering and help them come to terms with the loss of their mother.

Their welfare has been Dan’s sole concern, and his love for his kids has meant that he hasn’t been able to devote any time to himself.

SAS: Who Dares Wins appears on Channel 4 every Sunday at 9pm.

Marcin Porczynski, a schizophenric, was imprisoned indefinitely for the killing of Nikki Cross.