Caleb, played by William Ash, has recently returned to the village to plot against Kim Tate (Claire King) and get his hands on Home Farm.
The secret son of Frank Tate, Caleb was caught out, leading Cain to feel "incredibly stupid" for letting him in his life again.
As the conman will be found dead in upcoming scenes, Hordley explained Cain's potential involvement in his half-brother's murder.
"I think there is always potential for anything with Cain," the soap star told press including RadioTimes.com. "If he's pushed in the wrong direction or if he flies off the handle then anything can happen."
Cain is experiencing a lot of resentment over Caleb's deceit, explained Hordley.
"I think Cain was beginning to accept the fact that he had a brother and he was beginning to quite like that they were starting to get on," he said.
"It's a shame, as far as Cain's concerned, because once you let him down he isn't the type of person to give you a second chance."
As Cain has been responsible for various crimes over his time in the Dales, it won't be a surprise for him to be among the suspects of Caleb's murder.
"It's the nature of the show we are in that we often have these whodunnits and I've been in the lineup for many different things over the years," Hordley said.
"It's just another day in paradise for me."
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