Complex sentence: The injured one tries to escape in a car but Gautham shoots him and when the other one receives a call from his boss, he finds out that the boss is actually the old Taxi driver who gave him the Rubik's cube.
Split into simpler sentences: The injured one tries to escape in a car but Gautham shoots him. When his mobile receives a call from his boss, he finds out that the boss is actually the old Taxi driver who gave him the Rubik's cube.