The near-ultimate in budget-conscious "bottle shows" (all but two scenes are filmed inside Malcolm's Bouziki Bar; Pamela Bellwood and two firemen are the only guest actors; and much of the show is in flashbacks) finds Pete, Mac, Malcolm and Maggie trapped inside the bar with a very pregnant murder witness while mob hit men search unseen for a way in. Some sources give this episode's air date as August 13, 1978, when the show was run off as a summer series (and did very well in the ratings).
The series began a summer run (ironically, enjoying its best ratings since the first season and tremendously better than it had done in the fall) with an episode about kidnappers grabbing the brother of a photographic model -- the brother is a veterinary student specializing in large-animal surgery, which he is to be forced to use to remove diamonds from the hide of an African rhinoceros recently imported to Los Angeles. Watch very fast for Natalie Wood bidding her then-husband Robert Wagner (Pete) goodbye from a bathtub at about the 10th minute.
Soem interesting underwater (swimming pool) footage highlights this episode as Pete and Mac -- in full business suits and at their ages (over 70 for Eddie Albert) dive in to defuse a nuclear bomb threatening to take out a society party and much of Los Angeles to boot. This episode was broadcast on August 6, 1978 (possinly its first run) just before the TV news announced the death of Pope Paul VI.