I've been going over it quite a few times, but there are a couple recurring paralels between KOTCS and MacGyver and the Lost Treasure of Atlantis (MGLToA).
*** WARNING ! *** Those who never seen this MacGyver film, leave NOW as in this comparison I am revealing some plot SPOILERS. Sorry !!
In MGLToA, McGyver has to meet up with Prof. Atticus, in order to find clues to the lost city of Atlantis. During their quest, they actually stumble across an artefact, the Ark of Solon
. Well, well... gotta love these arks all around the globe
Deprived of academic support to fund his bizarre quest to find the 'Torch of Truth' and Solon's artefact, Professor Atticus sets out to underground catacombs in the Balkans where the 'cult of Solon' was probably preserved. After being discovered and detained by Serb/Croat/Bosnian/whatever paramilitary, they miraculously escape (of course) with a rocket-boosted jeep.
Funny detail: MacGyver fires of an overhead-fixed RPG launcher to blast the gates of the military camp ahead of their course ... IN KOTCS, MacGyver uses a handheld RPG too, in an attempt to cripple the Russian forest-cutter trackwagon (resulting in that cutting blade travelling - whooosh! - across their heads).
So, back at the 'Royal Academy for Archaeological Science', they sollicit the aid of Kelly to unlock Solon's ark... trying to solve the riddle "The Gods march in rank, and Hekatè (Demon of the Night) races in the heavens. Enter the Gates of Hades and the book shall summon the power of the Ancient Ones. Offer the Torch of Truth to the Temple of Ages and the Treasure of Atlantis shall rise."
When the Academy director comes to tell Atticus that he and MacGyver are being accused of having stolen the relic abroad, and says the 'Balkan Embassy' (? - last time I checked the Balkans are region, not a state... the producers must've meant Yugoslavia or something) claims its immediate return. Upon this, Atticus scoffs and replies: "You can't give it back to those butchers, it belongs to the world!". Now that staunch idealism to preserve world heritage echoes Indy's determination in The Last Crusade: "It belongs in a museum".
Then, the physical properties of magnetism
is both apparent in KOTCS and MGLToA: while trying to open the Ark of Solon, MacGyver accidentally learns that the box has a magnetic side to it, as McGyver observes his keyhanger to be sticking to the 'Sigma medallion' (sigma, the Greek 'S' for Solon) and indicates the ark is magnetic too. The medallion being the key to the ark, Atticus opens it but the box is empty.
After the Ark is stolen by a henchman, Atticus explains to MacGyver more about the Atlantians and Solon... And guess what: while this flamboyant and "more exhuberant version of Marcus Brody" (Atticus) scurries around his office, he passed a pile of books upon which a translucent, glass-like cranium rests !
The head itself looks quite normal, but the lengthy chin hints that it could be another predecessor to the homo erectus... Easy to miss in MGLToA, but oh boy did my jaw drop when I spotted that
Also, the artefact will reveal a hidden side as MacGyver's infamous Swiss pocket knife is pulled against the side of the crate by the magnetic field.
In KOTCS, we all remember Indy using gunpowder from gr enades and ammo shells, throwing it up in the air to track down the crate Spalko is looking for in hangar 51 at the U.S. Army facility in Nevada.
Then again, the booby traps, the first platinum punge-card computer being used, steam-powered technology, and the entire ending is all very Indy-like.
The basic plot end of MGLToA is that Atlantis's 'treasure chests' contain scrolls of the old philosophers and scientists, basically a priceless collection of knowledge.
At the end of KOTCS, when the Alien saucer/mothership takes of and 'cleanses' the valley beneath it (thus wiping out all trace of it ever been there), Indy reasons that the Alien race that once interacted with the Mayan/ Meso-american peoples were actually accumulating (meta)knowledge on an ethereal level...( that's why Spalko's cranium fries in the end, her brain can't cope with the cognitive flux !). But that's too much knowledge to erupt onto Professor Jones... they hightail out of the temple of Akator.
Yup, the same 'clue' regarding the treasure in the end is, both in MGLToA and KOTCS is: (off-world) knowledge.
It's funny that during a police investigation, it is mentioned that the illegal traffic in stolen artefacts is a huge problem, second largest to narcotics (maybe that was so in 1994, but now it is surely arms and human trafficking).