This is the only time in the series which David Doyle (Bosley) receives third billing in the opening titles.
Shelley Hack's debut as Tiffany Welles. She appears at the 13 minute mark. Season 4 ratings plummeted due to repeating plots from previously aired titles, and because, week after week, most storylines invariably concentrated on Kris Munroe, to the point of viewer fatigue. Some uninformed fans of the departed Sabrina blamed newcomer angel Tiffany Welles, but it simply was because Edward J. Lakso strongly disliked Shelley Hack, due to behind the scenes politics and his dalliance with Cheryl Ladd, who unfortunately was equally antagonistic towards the newly-cast and statuesque blonde beauty. Thus, Ed refused to properly introduce Shelley's character or allow scripts to be written with Tiffany as featured angel. Indeed, the premiere for season 4 saw Tiffany---who, it ought to be noted, was very well received among viewing audiences---as hardly more than a lovely background prop, so to speak, while the two-parter episode, once again, revolved around Kris.
The ditzy blonde whom Kelly and Kris mistake for Tiffany at the start of the episode is played by Judy Landers. Landers also appeared briefly in season two's Angels on the Run (1978) and her sister, Audrey Landers, had a major role in season three's Teen Angels (1979).
The opening credits are in a completely different style from the show's normal opening. It dispenses with the whole "Once upon a time..." intro, and starts with the silhouette and explosion that usually comes at the end of the opening. Then, over cruise ship scenes (instead of an action montage), credits for each of the stars, "and introducing Shelley Hack as Tiffany Welles", finishing up with the silhouette again (sans explosions).