So, Agent Gunn went out to personally pick up Mark? Mighty nice of him to do that. So at this point, I’m thinking that any notion of Mark doing undercover work just took the next flight out. And it’s mighty naive of Mark to confess (panel 2) that he’ll likely be more of a hindrance than a help to Agent Gunn. But Mark’s got optimism, eagerness, and grit on his side (and maybe in his shoes, as well). 

You might be more perceptive than I am (which is not saying much); however, I’m not really clear just what Mark’s function is going to be. Heck, we don’t even know what Agent Gunn is really investigating. Nevertheless, Agent Gunn has clearly accepted Mark’s assistance in some capacity, so there is still opportunity for hilarity, explosions, and a complete lack of mystery.