Irina Spalko was a KGB operative communist working for the Soviet Union. She was attempting to obtain the Crystal Skull in order to give the USSR an advantage over the Americans.
Ike was a nickname for President Dwight D. Eisenhower, staunch opponent of communism. "I like Ike" was one of his campaign slogans.
From the screenplay:
The barrel of Mac’s gun,...
Yes, it most likely is a reference to the Young Indiana Jones Chronicles. The specific adventure with Pancho Villa was shown in the first episode, the pilot "Young Indiana Jones and the Curse of the Jackal". It was also recut as the 6th film, Spring Break Adventure.
Lucasfilms considers most things in canon, with the feature films being the highest canon, ...
I interpret Oxley's answer as "the aliens went to another dimension."
This makes sense as a follow-up to his earlier dialogue with Mutt Williams:
Williams: "What are they? Spacemen?"
Oxley: "Interdimensional beings in point of fact."
Marion sees the tree a few moments earlier.
From the script (page 102A):
Marion ducks as the Russian GUNFIRE SCREECHES off the metal sides of the duck.
But it allows Mutt and Mac to jump in from the other side,
Marion hits the gas and they take off toward the river. But they
soon reach a short cliff.
Marion stomps on ...
In response to this claim, a civic-minded scientist has subjected the
stunt to the rigors of scientific peer review and posted the results
on Overthinking It, a blog with a tagline of “where we subject the
popular culture to a level of scrutiny it probably doesn’t deserve.”
After a careful and extremely thorough crunching of the ...
Even though this was answered a while ago, here is more-or-less the same, but visualised.
Imagine two-dimensional beings. They live in 2D space, which we usually call a plane. There are infinitely many planes and some are parallel, i.e., they do not intersect. If you pick two of these, there is a space between those two planes (2D spaces), incomprehensible ...
The aliens have come from inter-dimensional space. Wikipedia narrates:
Spalko believes that the crystal skull belongs to an interdimensional being and holds great psychic power, and proves her theory by showing that the corpse stolen from the warehouse has an identically shaped skull.
It further says:
After the Soviets arrive, Spalko replaces the ...
The series is also referenced in Indiana Jones and the Kingdom of the
Crystal Skull, when Indy describes his adventures with Pancho Villa
(chronicled in the first episode) to Mutt Williams.
The first episode of the series was Young Indiana Jones and the Curse of the Jackal:
Indiana finally caught up again with this jackal shaped ...