Callum Monks made his first appearance on 18 August 2008. He is portrayed by Elliott Jordan.
Arriving in Walford in search of his father Vinnie, Callum is instantly attracted to Stacey Branning. Unperturbed by her rejections, Callum attempts to woo Stacey, despite discovering that she is married. He briefly dates Stacey's friend Dannielle Jones but only to make Stacey jealous. Stacey continues to reject Callum, but after her husband Bradley Branning angers her one night, she kisses Callum. Realising that her marriage is over, Stacey finishes with Bradley, allowing a casual relationship with Callum to begin. Their romance does not last, as Callum cannot bear to be around Stacey's mother Jean Slater, who has bipolar disorder. Blaming Jean for the relationship's demise, Callum aggressively tells her that she is ruining her daughter's life. When Stacey discovers this, she punches Callum and he reveals that his mother, who was also mentally ill, used to abuse him and lock him in cupboards when he was a child. He has scars on his legs from an incident where his mother attacked him with a wire coat hanger at the age of ten. Due to this and realising that Stacey would never leave Jean, Callum declares there is nothing left for him in Walford. He bids a final goodbye to Stacey and leaves to pursue Vinnie, who has already departed. The EastEnders website showed that Callum went to live with his father in Southend.