The catch is that you need to buy one full-price ticket in order to get the companion ticket for $15.
Starting Sunday at noon, you can buy the $15 tickets for shows scheduled April 21 through May 31.
And Crain's reports the deal is good only for "certain seats and performances" during the five-week window.
The separate Kids Night on Broadway program, now monthly, offers a free child's ticket with each adult ticket purchased at full price. Participating shows include "Shrek," "Guys and Dolls," "Hair" and the upcoming "9 to 5."