Castle - Season 3 Episode 16 -

Recently US-nationalized Syrian cab driver Amir Alhabi, who runs his own company with cousin Jamal, is shot in his cab after a 45 tour back to the start point with consulate 'security attaché' (spy) Fariq Yusef. Homeland Security Agent Mark Fallon takes charge after his keys lead to a storage unit with cobalt radiation feared to stem from a nuclear weapon. Castle is officially discarded but keeps in the loop, tracing a payment to Amir, which he believes a fake as cover-up, shifting focus to employed cab driver Kevin McCann.