[spoilers] Episode ideas for series 9

[Kirayuki]

I like the plane idea, but i think it would probably work better if the terrorists held the people on the ground in the airports terminal hostage and based it there.
They could say they had Hijackers on one of the flights that was currently airborne whilst holding the hostages on the ground. Double whammy.
Besides i think that it would be interesting to try and see MI-5 have people on the inside, (whoever really but it would be nice to see someone who isn't Ros or Lucas in this position. ), of the Hostage scenario trying to contact their colleagues and prevent an air crisis from occuring.
(It would also be easier to budget for )