Futility of keeping poor proles in suspense somehow shown at the outset (15)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

Futility of keeping poor proles in suspense somehow shown at the outset [*(PROLES) in *(SUSPENSE)] + S <hown> (“at the outset” means first letter only); “poor” and “somehow” are both anagram indicators