Watch: Nathan Fillion & Robert Downey Jr. Promote Avengers and Castle

A mini-promo starring Nathan Fillion and Robert Downey Jr. aired last night after Castle on ABC. In the spot promoting The Avengers and Castle as Fillion points out the similarities between Rick Castle and Tony Stark/Iron Man.

Watch after the jump:

I could watch that 30 second on repeat another couple (dozen) times.

As if I couldn’t get more excited for The Avengers to come out on May 4th. Now I’m wondering if there’s truth to those crazy rumours that Nathan Fillion has a secret cameo in the film.