The Normal People star plays the part of a firefighter named Sean in the psychological drama.
The Kildare actor has already been nominated for an Emmy for the role of Connell in Normal People, with the awards take place in LA on September 20.
His latest role went down a storm with viewers.
"Paul Mescal speaking Irish...I don't think I'll ever recover or love something as much ever again #thedeceived," one fan tweeted.
Another wrote: "Paul Mescal in a fireman uniform, speaking Irish and having a Donegal accent is everything I didn't know I needed."
The four-part series, which stars Irish actor Emmett Scanlan, already aired on Channel 5 in the UK last month and is meeting with favourable reviews from this side of the water.
The rising star has been hailed for another "charismatic" performance in the series, which was produced and written by Derry Girls star Lisa McGee and her husband Tobias Beer.
The 24-year-old plays the part of a Donegal fireman, who takes a shine to Ophelia, the young Cambridge star who falls in love with her professor (Scanlan).
When he suddenly disappears, she tracks him down to his home town in Ireland where she learns that his wife has mysteriously died.
Actress Eleanor Methven, who plays Mary in the series, previously worked with Mescal on Normal People and said it was obvious early on that he was something "quite special".
Co-star Catherine Walker who plays the part of Scanlan's wife Roisin, said she was "gutted" she didn't get the chance to work alongside the rising star.
"He'd shot Normal People and then he came to us. So it was his second job but Normal People wasn't released yet," she said.
"Our storylines don't cross; I'm gutted. So gutted. What an extraordinary show, what an extraordinary actor. I obviously met him on The Deceived. But we were on completely different worlds though. So our paths didn't cross acting-wise."
She added he was a "wonderful person...He's a very humble guy."