The actor told Entertainment Weekly that the concluding instalment, 'I'm The Good Twin', will answer many of the show's "big overlying questions".
© The CW
"I think the audience will be shocked with what we do and what we reveal," he said. "The stuff that we answer... would normally take maybe a couple of seasons to answer.
"Like the big overlying questions that we set up in the first episode - those are going to be revealed come the finale, so it's pretty intense."
Gruffudd also insisted that fans will not feel disappointed by a lack of resolution in the episode.
"There are a couple of things that are unanswered but nothing in a sense that you feel betrayed," he claimed. "There are a few avenues that I'd like to explore more, but with what we have revealed, it might be difficult to go down that avenue."
© The CW
The Welsh star added that he is still feeling "very optimistic" about a potential second season of Ringer.
"I'm seeing myself doing a second season," he admitted. "I haven't even thought twice about it.
"There's one element that hasn't been answered which will be enough to segue into next season, but a lot of the questions are, 'Well, where do we go now?'"
The first season of Ringer concludes this Tuesday at 9/8c on The CW. In the UK, the series airs on Sky Living on Thursdays at 8pm.
> Ringer star Ioan Gruffudd 'desperately hoping for season two'
> Ringer: 'It's Called Improvising, Bitch!' recap
Watch a promo for the Ringer season finale below:
