In July 1927, Jack (John Barrowman) catches an Italian immigrant named Angelo Colasanto (Daniele Favilli), who stole his visa at Ellis Island.
Jack falls in love with Angelo and helps him move to Little Italy, New York where they become lovers and pose as minor bootleggers for the Catholic Church.
The mysterious group are caught by surprise when they are sniped by Rex (Mekhi Phifer) and Esther (Alexa Havins), who both earlier became suspicious of Gwen's behavior and learned the truth from the last messages recorded from her contact lenses.
In the interim, Esther had contacted Andy (Tom Price) in Wales, who leads an armed police unit which rescues Gwen's family much to her relief.
By reducing the screentime of Rex and Esther and keeping Oswald and Jilly out of the episode, Den of Geek felt that the Jack-centric flashbacks "deepened" the Miracle Day narrative, and praised Espenson for her writing.
[1] The HD Room reviewer felt "Immortal Sins" was the best Miracle Day episode so far and praised the return to the "Time travel, aliens, last minute saves" plots of the earlier Torchwood series.
In conclusion Martin said that the episode made Gwen remember that she has a family and allowed the viewers to examine the two leads relationship, and references to the backstory was also a welcome relief and beyond all Eve Myles proved herself to be rather good at acting.