Many people assume piracy laws do not exist in Pakistan. This is false. With the introduction of the and strict anti-piracy laws (Copyright Ordinance, 1962), downloading copyrighted content is a punishable offense. While individuals are rarely targeted for casual downloads, the ISPs (PTCL, StormFiber, Transworld) are actively blocking torrent websites. Using VPNs to bypass these blocks does not make the act legal.
Believe it or not, the official rights holders have occasionally uploaded the first two movies for free. While the third movie is typically paid, you can it directly on YouTube Movies. download movie pk 3 bahadur
Since your keyword implies you want a file to keep on your hard drive, here is the legal workaround. Many people assume piracy laws do not exist in Pakistan