When season eight began for 7th Heaven, it became the first WB series to remain on the air for so long a time. In this season, the series also expanded beyond its traditional yearly quota of 22 episodes to include a 23rd installment. The previous season climaxed as minister Eric Camden (Stephen Collins) performed the marriage ceremony of his daughter Lucy (Beverley Mitchell) and police officer Kevin Kenkirk (George Stults), and Lucy's older sister Mary (former series regular Jessica Biel, now a "guest star") revealed her own recent marriage to Carlos Rivera (Carlos Ponce). These events spill over into season eight, as does the fallout of a fatal car accident involving Simon Camden (David Gallagher). Also, oldest son Matt Camden (Barry Watson), though no longer a regular character on the series, makes sporadic appearances as he weathers his first year of internship in a big-city emergency room -- not to mention problems in his marriage to fellow med student Sarah (Sarah Danielle Madison). Elsewhere, the relationship between youngest Camden daughter Ruthie (Mackenzie Rosman) and troubled preteen Peter Pietrowski (Scotty Leavenworth) hits a snag when Peter's birth father, Vic (Bryan Callen), comes back into his life -- a plot development that also bodes ill for Peter's mother, Paris (Shannon Kenny), and her current amour, Eric Camden's assistant pastor Chandler Hampton (Jeremy London). The connubial bliss of newlyweds Lucy and Kevin is threatened by the arrival of Kevin's contentious ex-wife, Mindy (Mindy Burbano). And a mysterious stranger named Martin (Tyler Hoechlin) insinuates himself into the Camden household -- and into the heart of Simon's former girlfriend Cecilia (Ashlee Simpson). Even more serious complications are linked with such real-life current events as the war in Iraq and the crisis in Sudan. Season eight ends with a two-parter wherein one couple considers breaking up, another tries to get back together, a third contemplates leaving Glen Oak for good, and yet another member of the Camden household prepares for motherhood.