Final answer:
The Supreme Court case Humphrey's Executor v. US in 1935 marked a shift from the idea that the President had absolute control over all executive power.
Step-by-step explanation:
The Supreme Court case where the Court moved away from the idea that all executive power rested with the President was Humphrey's Executor v. US, in 1935. In this case, the Supreme Court upheld the principle that certain executive branch officers could perform their duties without fear of removal by the President. This marked a deviation from the view that the President held absolute control over the executive branch of the government.