Alice's September Song is the 23rd episode of Season 2 of The Brady Bunch, and the 48th overall episode of the series. Written by Elroy Schwartz and directed by Oscar Rudolph, it first aired 12 March 1971 on ABC.
Alice's old flame, Mark Millard, re-enters her life, wanting to sweep her off her feet, then presents her with an investment proposal that Mike senses may be too good to be true.
Alice receives a surprise telephone call from Mark Millard, her dashing former sweetheart from school whom she hasn't seen since those days, who wants to see her. Despite casually dating Sam, Alice decides to go out with Mark to see if that old spark is still there. Mark is as handsome and charming as Alice remembers. He wines and dines her, so much so that she thinks he will soon pop the question, which if he does, she is not sure how she will answer, partly because of Sam. The question he pops is about a business investment opportunity, which excites Alice as well. Later she casually mentions it to Carol, and Carol curiously asks about the business involved. Alice has no idea, as she had got caught up in the moment, and didn't think to ask. Carol tells Mike about the suspicious investment, and Mike does some background checking on Mark Millard. He eventually uncovers that Mark is trying to scam Alice, as he has a chronic gambling problem, and uses gullible female partners to support himself, and he's already scammed six other women, five of whom he's now paying alimony. Carol and Mike tell Alice, who feels stupid for almost buying Mark's scam. Mark arrives, and Mike reports to Mark that a friend from the D.A's office is on his way over for questioning. Mark tries to escape, but runs into Sam the Butcher, and a frozen leg of lamb, and is knocked out. Meanwhile, the boys, with Mike's help, work on building a model airplane, but can't get it to fly in the yard. Sam and Alice take them and the girls on a picnic in the park to fly it.