At stake ... or where you may find 17-, 24-, 38- and 50-Across

ONTHELINE

Think of a phrase describing something at risk or the edge of a fishing rod’s path.

This clue plays on two meanings of "on the line." First, it hints at something "at stake" (like a bet or risk), where you might say your reputation is "on the line." Second, it literally points to the answer being found on the line—the numbered clues (17-, 24-, 38-, and 50-Across) all share the same row in the grid, forming a straight line where the answer is written. The pun ties the phrase’s figurative and literal senses together, making "ONTHELINE" fit both interpretations perfectly.