‘Do No Harm,” NBC’s new Jekyll-and-Hyde drama, is pretty darned silly. Steven Pasquale plays a brilliant neurosurgeon who has what appears to be Dissociative Identity Disorder. By day, specifically from 8:25 a.m. to 8:25 p.m., he is the compassionate Jason Cole, who can move administrative mountains to save a little girl’s eyesight. By night, he is the aggressive, womanizing, drug-abusing Ian Price, who wrecks hotel rooms and steals cars. The digital clock blinks 8:25 p.m., Jason’s eyes become black marbles, and J. Cole — get it? get it? — goes into hiding.

Like Tara on “United States of Tara,” a woman with DID who had a full coffee klatch of alters, Jason is rebounding from a mysterious trauma in his childhood when, he says, he “hurt someone badly.” I’m guessing the nature of that event — which probably occurred at 8:25 p.m. — will emerge as the series develops. There will be back story. But “Do No Harm” isn’t a psychological exploration so much as a medical drama with a gimmick. Despite the presence of a DID support group that Jason refuses to attend, and a sponsor played by John Carroll Lynch, the episodes focus on the brain surgery of the week and Jason’s frenetic struggle to protect his life from disaster.