Natalie Schafer (Mrs. Howell) does not actually appear in any scenes with the lion in this episode. Instead a double is used for all scenes in which Mrs. Howell appears in the same shot with the lion. This includes the scene where the ladies run from the lion as it is perched on a rock, and the scene where the lion enters the Howell's hut with Mrs. Howell inside.
When filming with the lion, the actors were warned not to make loud noises or sudden moves. When the lion was on one of the Howells' bed, Bob Denver touched him and jumped and yelled. The lion pounced, but the bed was on wheels, so the bed rolled out from under him. The lion narrowly missed Denver. The animal trainer didn't want any of that information to be given out because it would ruin his career.
When trying to draw the lion into the net trap outside the huts, why does everyone not involved with the trap stand so close, on open ground at that? Not to mention it would take more than the strength of the Skipper and Gilligan to keep him held up in the net; surely the Professor would've said something about that.
Mary Ann: What in the world are you trying to do?
Skipper: Believe it or not, I'm trying to learn how to juggle. But I just don't seem to get the hang of it.
Mary Ann: I know. Gilligan wants me in his circus act, too.
Skipper: Hey maybe we can do an act together.
Mary Ann: Like what?
Skipper: We'll have a hatchet-throwing act. You can be my assistant.
Mary Ann: All right. Are you very good at it?
Skipper: Well I couldn't be any worse at that than I am at juggling.
(Mary Ann runs away while the Skipper's back is turned.)
Mary Ann: Hi Skipper.
Skipper: Hi Mary Ann. Where is Gilligan? He took some of my planks and I need them.
Mary Ann: He's over there. He took my washtub, too. He's using it for his circus act.
Skipper: For his what? His circus act?
Mary Ann: His circus act. Gilligan's.
Skipper: I'm gonna go over there and straighten that boy out.
Mary Ann: Skipper, I wouldn't do anything rash.
Skipper: I'm not gonna do anything rash, Mary Ann. I just want my planks back. I'm fed up with Gilligan and his ideas.
Mary Ann: Make sure [the lion] doesn't get fed up with you if you know what I mean.
Skipper: I see what you mean.
Lovey: Thurston, darling, don't you think a circus is rather provincial?
Thurston: On the contrary we'll play, before the crowned heads of Europe, my dear.
Lovey: Oh if that's the case, then I want to be in the show myself. Well darling, what are you doing with my eyebrow pencil?
Thurston: (with a pencil mustache) I am making myself dashing and debonair. How is that?
Ginger: Oh Mr. Howell, you look dashing and debonair.
Thurston: You look "d" and "d" yourself.
Ginger: It's my new high-wire outfit. Do you like it?
Thurston: It packs plenty of voltage.
Lovey: I think it's rather shocking myself.
Ginger: I guess I'd better go practice. I've gotta lose part of my wiggle so I can stay on that tightrope.
Ginger: Gilligan, thank you. You saved my life.
Gilligan: You don't have to be afraid. [Leo, the lion] likes girls.
Ginger: Yeah for dessert.
Mary Ann: Isn't it awful the way women have to sit and worry and wait until the men decide to show up?
Ginger: Usually I don't have to wait very long.
Professor: Why don't you go back to camp and stay with the women?
Gilligan: If I go back to camp, then the girls'll think I'm a coward. Besides you guys know I'm not afraid of any old lion. All they are, are fur and bones and muscles and long claws and big white fangs with big white teeth and I'll meet you back at camp.
Gilligan: (referring to Leo) Look at him King of the beast, a jailbird.
Theme of episode: You can never be sure you've taken the "wild" out of wild animals.