In 2012, ISRO discovers an extrasolar planet with conditions similar to Earth. On the chance that it contains intelligent life, ISRO transmits a powerful signal from a communications array, which will be boosted by a satellite in the orbit.
By 2015 five alien ships arrive in response to the ISRO signal and land in the Arabian Sea. After sinking a USN carrier group that patrolled in that area, the alien ships are heading towards Mumbai, IAF reacts to the threat and scrambles Super 30 MKIs with Brahmos cruise missiles, Rafales with Scalp cruise missiles, covered by LCA MK1 with Derby and Python V AAMs.
Pakistans government understands, that this is a threat not only for India but for the whole region and beyond all issues both countries had in the past! PAF sends JF 17 Block 2 with Raad cruise missiles and C-802, covered by J10Bs with SD 10B and MAA-1 AAMs. Both attack groups joins over the sea with IN Mig 29Ks, armed with 2 x Kh 35 and AAMs and starts the first joint attacks to protect South Asia!!!