Episode two of the new RTÉ thriller has viewers guessing who killed Denis.

Everyone is still a suspect after watching 'Smother' episode two. Well, one of the Ahern family seems to be the primary concern for the Gardaí for now. By the end of the episode, they're taking Val's lover Carl in for questioning at the station. After all, he did go for a run in the middle of the night that Denis was killed...

However, it could all just be a red herring. There are a number of characters involved which could have been the culprit. Another one who is up for contention is Grace, who has no memory of what happened on the night. Through her backstory of the abortion, with her being angry towards her parents due to the divorce, and her now knowing her father had planned to sell her café, it's a lot for a person to have handled on the night in question.

Val is in complete denial that Grace had anything to do with her husband's death. However, she is also not able to accept that her daughter walked out into the sea of her own accord, which led to her life being saved in the hospital. She believes that at the end of episode one, Grace was just out for a swim when she got a cramp.

Twitter has been going wild with theories as to who caused Denis' death. Here's who viewers think are the chief suspects, as well as some praise the cast and the series has been getting so far.

The Co. Clare coastline was once again a talking point for some viewers of 'Smother' episode two, with the wind and rain being a constant bit of fresh air for the cast.

Who do you think could be the "cliff killer"? Let us know in the Facebook comments. Tune into 'Smother' on RTÉ One next Sunday at 9.30 PM or watch 'Smother' episode two on catch up on the RTÉ Player.