Related Clues:

• Suspenseful
• Not easy
• Future perfect, for one
• Pluperfect, e.g.
• Noun concerning verbs
• Needing a massage
• Needing kneading?
• Far from relaxed
• Lacking slack
• In knots
• In danger of snapping
• Past or future
• Present, for one
• Hardly relaxed
• Volatile