Dr. Yes! Begins as a literal white-coater, with Marc Brock and his comely assistant wearing nothing but white coats (and a pair of panties - on her, not him) as they work on his sex experiment. You have to wonder if they just didn't want to go to the laundromat that day, or if they never wore clothes under those coats, or if Dr. Brock was so sure that day was the day of discovery, he barred clothes...needless to say, this isn't the point of the film, but it's more interesting than most of the content.
The 'plot' is wholly unnecessary, between the lab intro to the decision to use the aphrodisiac to sex up a graduation party with students and faculty. There was no character buildup, and no real tension to take them from sitting around to where their clothes magically disappeared as soon as they sip from the drugged drinks.
That isn't to say the film is unwatchable - if you want some burgeoning action for the more accepted hardcore era (you can still see they're somewhat hesitant about penetration), or return to the days of mostly natural bodies and believable intimacy, there's something to enjoy. I'd still say it's only worth sitting through for completion's sake.