In Along Came A Spider, Alex deals with the kidnapping of two wealthy children at the hands of Gary Soneji.

In Kiss The Girls, Alex battles the serial killers Casanova and The Gentleman Caller, who "collect" beautiful women, including his niece Naomi.

In Jack & Jill, Alex goes up against three killers: two who kill high-profile people and one who kills children.

In Cat and Mouse, Alex engages Gary Soneji again and after dealing with him crosses paths with another killer, Mr. Smith.

In Pop Goes the Weasel, Alex matches wit with a serial killer named Geoffrey Shafer, who happens to be a British man with diplomatic immunity.

In Roses are Red, Alex goes against a criminal calling himself The Mastermind, who commits several brutal bank robberies.

In Violets are Blue, Alex goes against a cult of vampires and learns the true identity of the Mastermind, whom he takes down.

In Four Blind Mice, Alex and his friend John Sampson investigate three killers who are framing seemingly innocent soldiers from the Vietnam War.

In The Big Bad Wolf, Alex, now a member of the FBI, tries to stop a Russian mobster known only as the Wolf.

In London Bridges, Alex tries to stop the Wolf once and for all, but the Wolf has enlisted the Weasel, Geoffrey Shafer, to help him take Cross down.

In Mary, Mary, Alex tries to stop Mary Smith, a psychopathic killer targeting Hollywood stars and powerbrokers.

In Cross, Alex, who has left the FBI to open up a private psychology practice, and John Sampson try to stop The Butcher, a serial rapist/murderer who may be somehow connected to the murder of Alex's wife Maria in 1993.

In Double Cross, Alex, still in private practice, rejoins the MPD as a special consultant to the Major Crimes Squad and is joined by John Sampson and new love interest Det. Brianna Stone in an effort to stop the DC Audience Killer, a serial killer with a flair for showmanship who may also have some connection to a previous Cross nemesis, The Mastermind.