There are three offensive players and three defensive players
#1 passes to coach
Defense rotates to proper positions (help and gap/deny)
Coach passes to #3
Defense rotates to proper positions (help and ball)
#3 drives to the basket as x3 allows him to
x2 helps on the drive, outside of the lane
x1 covers down and protects baseline
The drill is continuous depending on how many reversals you want
Rotate on the air-time of the ball
Communicate all of your defensive actions
Jump to the ball on the pass
On the drive, the help defender should stop the ball outside of the lane
The bottom man of the "I" made on the help line should be the one to help on the drive
The top man of the "I" made on the help line should cover down to protect the basket and baseline pass (get to the tip of the rim)
You can make this drill competitive and also add players (i.e. 4 on 4, 5 on 5)