In new scenes, the pair reunite following a big row, which comes after their break-up a few years ago.
However, speaking to TV Times, Charles has admitted that he and his co-star have been "waiting a long time for this moment".
"We suggested it numerous times because the audience have been screaming for it," he revealed. "So when we got the green light for Jacob and Connie to rekindle their romance, it was very exciting!
"It's most definitely worth the wait, I can assure you!" Charles continued. "It's one of those moments where you feel the tension and intensity between them – that animal attraction. It's definitely a hot, steamy moment!
"In our discussions about these scenes, Amanda and I agreed that we wanted to deliver something powerful. I can't stand superficial or very choreographed kisses in romantic moments, it kills the believability.
"So we understood that any kissing scenes would be done with intensity and as organically as possible. Fortunately, we got these scenes filmed before lockdown."
The moment will inevitably lead to questions on whether Jacob and Connie could get back together for good, Charles adding: "I know that I want their long-awaited reunion to be a permanent one.
"If I had my way, Jacob and Connie would be married! They'd have a beautiful white wedding and live happily ever after. But the writers won't be having that and I've already accepted it's not going to happen!
"Yet I like to think there's going to be a steamy, hot, intense period for as long as it lasts between them. They've both gone on interesting journeys, so I'm really curious to see how things play out this time."
Casualty airs it's final episode before a hiatus this Saturday (August 22) on BBC1.
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