S4·E1 Five Days in the Death of Sgt. Brown (II)

While in Los Angeles to testify for a trial against gangster Frank Harmon, Ed is shot and falls off the balcony of his hotel room. He is then taken to the Craig Institute where he undergoes emergency surgery. Although the bullet wounds were non-life threatening, Ed suffers a broken back in the fall and some damage to his spine. The scarring leaves him paralyzed and only an experimental surgical procedure is the only option to regaining his mobility. Also, even though all the evidence points to Harmon, Ironside has doubts that he was the person responsible for the attempted hit. Also, the chief begins having flashbacks to the night he was shot and paralyzed.

The crossover starts on Ironside S04E01 Five Days in the Death of Sgt. Brown (I).