Authorities believe that a Colorado dentist murdered his wife by lacing her pre-workout protein shakes with arsenic and cyanide. Court documents say that James Toliver Craig poisoned his wife so he could be with a woman he was having an affair with. The 45-year-old was arrested on Mar. 19 and was booked into jail on first-degree murder charges. His arrest came four days after he drove his wife to hospital because "she was complaining of severe headaches and dizziness." Police began investigating Craig after discovering he ordered potassium cyanide even though he did not need it for his work. Investigators believe James Craig put arsenic in a protein shake he routinely made for his wife for their workouts. James Craig is being represented by the public defender's office, according to court records.