"The Beast Within" is the first aired episode not to be written by Kenneth Johnson, and is the debut of the series' longtime writing/producing duo Karen Harris and Jill Sherman (now known as Jill Sherman Donner, after marrying actor Robert Donner, whom she met as a guest star on this show). And it's admittedly not very impressive. Johnson wanted to get away from the lowbrow action of other comic-book shows, and now we have the Hulk fighting a guy in a cheap gorilla suit. It's undermined by the fakeness of the gorilla, and by its annoying habit of referring to baby chimps as monkeys (which is pretty much tantamount to calling a bear cub a badger, taxonomically speaking). An actual vet would not make that mistake.
Also, Dr. Baxter isn't a very perceptive scientist, is she? Here comes this guy named David Bradburn who's inexplicably a scientific genius and is intimately familiar with the work of Dr. David Banner, and she never seems to notice the similarity. Plus, she gets a good look at the zoo logo on the Hulk's torn shirt when he's carrying her, but she doesn't seem to make the connection. This is the first time, I think, that the Hulk kept his shirt on throughout, and it was a poor time to start.
There were some continuity issues in the first Hulk-out. Beforehand, we'd heard an announcement that the zoo would close in 20 minutes. Then Carl took David to the lab and trapped him there, he Hulked out, and there was enough time for the cops to be called in afterward. Then the Hulk's rampage continued and we saw a tour tram that, judging by the driver's spiel, was only just starting its tour. That doesn't make sense. The zoo should've been closed by then. At the very least, the scene with the cops in the lab should've come after the Hulk's antics with the zoo guests.
But the tiger cub totally stole the show. Aww, it's trying to climb back in his lap! Awwww!
It was a missed opportunity to have the Hulk change before getting injected with the aggression-heightening formula. The Hulk even angrier than usual? That could've been an episode in itself (although we do get one or two episodes like that later).
A lot of familiar faces in the guest cast, a couple with other superhero connections. Caroline McWilliams (best known as Marcy from Benson) would appear in a 1996 Lois and Clark episode, while Dabbs Greer (Dr. Malone) had been in the very first Superman TV episode as the man Superman rescued in his heroic debut, as well as returning in two later episodes. Greer would also appear in Filmation's Shazam! (as a character named "Seldom Seen Slim," of all things) and The Greatest American Hero. The villainous Carl, Richard Kelton, has no other superhero-show credits, but he played the Spock-parody character Ficus in the sci-fi sitcom Quark.
While watching this, it occurred to me to wonder: Why was it so common in the '70s to think that showing action in slow motion made it more dynamic? By modern standards, it seems kind of sluggish. I think it pretty much started with The Six Million Dollar Man, when they figured out that speeding up the film looked silly so they had to paradoxically show superspeed through slow motion instead, but it seemed to catch on elsewhere. Granted, Kenneth Johnson probably picked it up from his prior work on 6M$M and The Bionic Woman, but I think its use extended to other shows of the era as well, including Wonder Woman sometimes.