D.O.A.

Dexter Cornell, an English Professor becomes embroiled in a series of murders involving people around him. Dexter has good reason to want to find the murderer but hasn't much time. He finds help and comfort from one of his student, Sydney Fuller.
Someone poisoned Dexter Cornell. He's got to find out who. He's got to find out why. He's got to find out now. In 24 hours, he'll be Dead On Arrival.