When the thugs do the drive-by shooting at the outdoor pool table, they're driving the car that is actually Steve McGarrett's 1968 Mercury.
The screenwriter seems to have confused the Bushido (samurai) with the ninja (ninjitsu). The Samurai were not a secret society.
After 41 minutes of the show, the phone rings in McGarrett's office. He answers the phone, but it continues to ring for several seconds more.
At the end one of the two cops who posed as Bushido puts handcuffs on just one of Tokura's wrists but never puts the second pair on before getting the car when it would be much more difficult and more dangerous.