Mitchell told TV Week that his alter ego, who started taking drugs in an attempt to heal his knee injury, will collapse at the beach after training "too hard".
"Romeo is in a fragile state," he further explained. "He feels a sense of being alone and he's just not thinking straight.
"Without him realising it, the steroids have started to have an effect on him and he's been snapping at a few people."
"Romeo and Indi have had a few obstacles in their marriage. I think they both want to reunite, but the timing has to be right and both of them have to be willing to give it another shot," the actor added.
Home and Away airs these scenes next week on Network Seven in Australia and in November on Channel 5 in the UK.