Casualty star William Beck has opened up about the devastating scenes which saw his character Dylan Keogh say goodbye to his longtime loyal canine companion Dervla.

Fans of the show deemed it the “saddest ever” death in the long running BBC medical drama as Dervla was euthanised after developing an aggressive cancer.

Pondering on the fan reaction exclusively to Express.co.uk William ruminated: “Aside from the positive feedback [scenes like that make you] realise just how something so the opposite end of the drama [can move people].

“It’s away from all the stunts and the accidents and catastrophes of the show. [But] sometimes something so straightforward and every day as doing the right thing for one’s pet, even though it involves something sad, I think continuing drama can do that very very well.”

The heartbreaking scenes in which Dylan made the difficult decision to let Dervla go were shot at night and William says this also added to the emotion conveyed.

“When you’re starting out as an actor the idea of night shoots seems impossibly romantic and the truth is they are impossibly romantic.

“Getting up and working, doing this job in the night. Everybody’s tired and tempers get fractured,” he admits. “In those circumstances the work you produce just has a different quality to it.

“I mean we’re dressing up and pretending for a living and it is amazing what you can make it look like. Those were brilliant scenes,” he reflects.

The heartbreaking scenes which aired on August 3 saw Dylan initally struggle to accept the vet’s recommendation to put Dervla down citing his own experience as a doctor fighting for his patients.

However, he eventually relented and gave permission for the procedure, rushing from his shift in Holby ED to hold his “best friend” as she slipped away.

The vet explained they had given her something to keep her calm prior to the medication to put her to sleep. “She’ll slip away quickly and won’t be uncomfortable,” they assured him.

A tearful Dylan said his final goodbyes telling Dervla through tears: “You’ve been the best friend I ever had.” He then stroked her gently, reassuring her it was OK as the medication took effect.

Following her death he was then shown sadly walking back to his car carrying her lead. He encountered nurse Sophia Peters in the car park who hugged him and told him it was OK.