Related Clues:

• Suspenseful
• Not easy
• Under tension
• Future perfect, for one
• Pluperfect, e.g.
• Pulled tight
• Tight, as a drum skin
• Noun concerning verbs
• Needing a massage
• Tightly strung
• Not lax
• Slackless
• Needing kneading?
• Far from relaxed
• Lacking slack