When Beaumont and his goons show up at the museum to switch the forged painting with the real one, they make no attempt to shield the painting (or their own faces!) from view. It's nighttime, but anyone walking by could easily see them walking in with a painting and become suspicious and/or be questioned later by authorities.
When Lambert created a diversion at the museum (by throwing a rock through the window), there was no alarm at all...in a museum with priceless paintings! The same is true when Jaime crawled through the window, as well as when she took the painting off the wall.
Pierre: I haven't any real talent anyway. Every time I look at the masters, their genius just defeats me.
Jaime: Pierre, the masters - they were just artists doing their own thing in their own time. Now, Van Gogh and DeJon - they never heard themselves called masters; that all came later. You gotta give yourself a chance. I think you're extremely talented - I really do.
Pierre: You have that much faith in me?
Jaime: Yes, I do! But what's important is that you have faith in yourself. That's what's gonna get you through.
Pierre: Jaime, what are we doing here?
Jaime: I'm trying to work it so that... so that Beaumont will deliver the fake painting to Moreau.
Pierre: But he's in there now, switching it for the real painting.
Jaime: Wellllll... maybe he is, maybe he isn't. Listen, in exactly three minutes, what I want you to do is throw a rock through one of these windows, okay?
Pierre: What for?
Jaime: 'Cause I'm gonna need some confusion, that's what for.
Pierre: Confusion? But I'm already confused.
Pierre: A public place is better. I can judge [Beaumont's] reactions, and if I think he's not sincerely forgiving me, I can call the gendarmes.
Jaime: One trick. One... little... trick... and I promise you, I'm gonna call Goldman.
Pierre: Jaime! Don't you trust me?
Jaime: Does a chicken have lips?
Though credited, Martin E. Brooks does not appear in this episode.