I'm stuck on the last four clues, if someone could help?
20d: Harry's TV drama (6) - H_S_L_ - I think it's HUSTLE but I don't understand why
29d: Daredevil as a result of a fever (7) - _O_H_A_
37d: Spend out on large outside plant (7) - S_L_R_E
56a: Strict author hasn't finished (5) - S_E_N - I think that this is STERN but again don't know why.