Possible Clues:

• Perform in the theater ... and what can be done to the end of 17-, 25-, 37- and 48-Across
• Go over the top, or a hint to 17-, 23-, 37-, and 48-Across
• Perform excellently for the audience
• Give 'em the old razzle-dazzle, say
• *Ham it up for the camera, say
• Perform excellently (Malinda Lo)
• Fake it