Aside from some weird giggling, this is a very good episode--quite original and worth your time. It begins with learning that a space ship has landed and a couple folks were killed by the two aliens. However, apart from that, nothing has happened...nothing. While the government would like to just blast the ship, they dare not--as it appears as if the ship has some nuclear material and blowing it up could trigger something drastic. So, in a weird and difficult to believe twist (just suspend disbelief with this one), they get a master agent (Robert Duvall) to agree to undergo surgery to make him look like one of the aliens. The plan is to then have him pretend to be one of the aliens who crashed there previously. Sure it's far-fetched but interesting--particularly when you see what this agent does and how the aliens respond to him. Not a brilliant episode but one that is strikingly original and a worthy addition to this excellent series.