B-town hottie Kareena Kapoor is the second cousin of director Siddharth Malhotra as Kareena's...

This holds true, even though the director denies it.
“There's no similarity between ‘Phone Booth’ and ‘Knock Out’. The only similarity is that the guy (Irrfan) is trapped in a phone booth, but the similarity starts and ends there. ‘Knock Out’ tells an entirely new story," Shankar said.
Starring Sanjay Dutt, Kangana Ranaut, Irrfan Khan and Gulshan Grover in pivotal roles, the comedy film has been made on a whopping amount of 300 million. Sanjay Dutt plays a negative role in ‘Knock Out’, while Irrfan helps in adding humor to the movie.
The story
Talking about the storyline of the movie, ‘Knock Out’ revolves around the male protagonists Sanjay Dutt and Irrfan Khan. Sanjay portrays the role of a shooter, who owns a large number of advanced weapons and works independently. He trusts no one, but himself.
Irrfan Khan plays the role of an investment banker, who is at the helm of affairs in the banking sector. He is very arrogant and the shooter aims to set him right.
Kangana Ranaut plays a television reporter and helps Sanjay in showing the story of a banker to the whole world in a live broadcast.
Actors excited about movie
Sanjay said, “When Mani narrated the script, I was raring to go. After the first day of the shoot, I realized I was doing the most difficult thing, I had to imagine Irrfan Khan was in front of me, and deliver dialogues without seeing him and his reactions.”
The movie has both the male characters in a new look. While Sanjay sports a small beard, Irrfan has grown hair.
Talking about his character, Irrfan said that it was tedious as throughout the movie, the other person was not in front of him, but on the phone. He added that he was very excited about the movie.
Overall, the movie seems average and there is no harm in watching it.