In 1976, Landry passed for 2,191 yards and 17 touchdowns and was named the NFL's Comeback Player of the Year.
After setting a couple of passing records with the Lions, Landry moved on to play for the Baltimore Colts for three seasons where in 1979, as a member of the Colts, he played brilliantly despite a 5–11 record after a season-ending injury to starting quarterback Bert Jones. He passed for a career best 2,932 yards and 15 touchdowns that season. He then played for George Allen on the Chicago Blitz and Arizona Wranglers in the United States Football League (USFL) in 1983 and 1984. He started one game as an emergency quarterback for the Chicago Bears in 1984 before retiring as a player.
Landry was also notable as a rusher, in addition to his passing. He rushed for over 2,600 yards and 21 touchdowns in his career, exceeding 500 yards on the ground in both 1971 and 1972, as well as averaging ten yards per carry in 1970 and scoring 9 touchdowns in 1972. He currently ranks third on the all-time Lions career passing yardage list (12,451), and ranks second in touchdown passes with 80.
The following year, Landry returned to the Lions as quarterback coach, helping them to become the top offensive unit in the NFL and guiding Scott Mitchell to record-setting passing numbers that season. He retired from coaching after the 1996 season to become a local radio host.