Actually, what Iran wants is mostly for their naval borders to be respected.
And then of course, parts of the Iranian establishment also want old mates freed who're held in other countries' prisons from back in the time when they used terrorism against foreign-based Iranian opposition groups as a means of internal politics. Not that I approve of that.
I don't see any reason to doubt that these guys did indeed stray into Iranian waters.
Lewis, you are acting really strange.
There is absolutely no rational reason to believe the Iranians!
There were a plethora of witnesses who agree the Brits were in Iraqi waters.