When fatal stabbing fails to kill him, Alfred Cahill becomes convinced that he has been chosen by a higher power to wage a crusade against 'perversion', and cuts a bloody path through Paris, murdering prostitutes and pimps, and endangering an old friend of Tessa's who has become a call girl. MacLeod tries to explain Immortality to Cahill, but he can't get through to him, and finally is forced to take his head.
Series clips illustrate family recollections as the kids put together a scrapbook for Vivian and Philip, who want to renew their vows on their anniversary.
Richie meets a beautiful young woman who leads him into the world of haute couture. His youthful jealousy causes him to run afoul of a world-class fashion designer, a deadly Immortal.
A day at the circus reunites MacLeod with a former lover, the Immortal femme-fatale, Amanda, who has always meant big trouble for him. Amanda, meanwhile, is in trouble of her own as her former partner, Blaine, has escaped from prison and wants her head. She plays the two Immortal men against each other, drawing MacLeod into a daring, high-stakes burglary she and Blaine are plotting.
Will lands a spot in a comedy showcase after accompanying a comic friend to an audition.
Grace Chandel has been a Good Immortal, working for the betterment of mankind as a midwife, doctor, and scientist over the centuries. Her one weakness is another Immortal, Carlo Sendaro, a former lover who is obsessed with her and refuses to let her go. He slays Grace's current (mortal) lover and, when she refuses to run off with him, frames her for the killing. She turns to her old friend Duncan MacLeod for help.
A mysterious death at the Paris Opera re-acquaints Duncan MacLeod with one of the strangest Immortals he has met in his many travels over the centuries. Ursa is a hulking giant — more beast than man — who Duncan rescued from persecution centuries ago, delivering him to sanctuary in an abbey. The abbey has long since been destroyed and Ursa now lives under Paris. He has become enamored of a past-her-prime opera singer who tries to use Ursa's innocent soul to murder her rival.
Heavyweight boxing champ Riddick Brown wreaks havoc with Carlton’s mind and Will’s face at a funky cafe-casino in Nevada, where the cousins have stopped on their way to check out a college for Will.
MacLeod stumbles across the trail of an Immortal, Xavier St. Cloud, who has lived in hedonistic splendor down through the ages by remorseless robbing and killing innocent men and women. MacLeod had nearly fallen victim to this remorseless killer behind the front lines during World War One, when Xavier used poison gas to loot a payroll truck. He uses even deadlier gas in modern day Paris, and MacLeod must track him down before he kills again. He succeeds in defeating Xavier, but the Evil Immortal escapes with his head. In a humorous yet touching subplot, Richie falls for a glamorous older woman, not realizing she is married, and Tessa must disentangle him from the woman's clutches.
Vivian’s baby is a week late, but family members and her visiting sisters are nowhere to be found when it’s time to rush to the hospital.