In September 1928, Warner Bros. Pictures purchased a majority interestin First National Pictures and from that point on, all "First National" productions were actually made under Warner Bros. control, even though the two companies continued to retain separate identities until the mid-1930's, after which time "A Warner Bros.-First National Picture" was often used.
The play, "Ambush," opened on Broadway in New York City, New York, USA on 10 October 1921 and had 90 performances. The opening night cast included Florence Eldridge as Margaret and Frank Reicher as Walter.
Vitaphone Production reels #4872-4879 and #4841 (trailer)