Oh, what I would pay to know what was going on in the heads of Interpol agents in the Frame Up Job, like imagine being in their shoes: you come to an estate sale because a never-before-seen painting of a famous artist got stolen, probably a standard affair in their business. But then you watch your boss, the infamous James Sterling, completely spiral over the course of one afternoon because a couple has him absolutely wrapped around their fingers.
One second, he pins them as prime suspects on sight; the next, he's working alongside them to solve the case. The man (who faked being an undercover Interpol agent, by the way) says the guy whose estate is being solved was actually murdered? Well, in that case, it's got to be murder!
Quickly, you concluded that the butler did it; all is well and good. You recovered the mystery stolen painting (with the help of a couple you're growing surer by the second are some flavour of criminals, but Sterling seems to be chill with that fact, so it's probably fine). Now all that's left to do is to tag it as evidence and wrap this whole thing up - oh, what did you say? Your boss's rival(?)-turned-suspect-turned-partner-turned-general-pain-in-the-ass vaguely implied that something about their procedure might be a little bit iffy? Apparently, that alone is enough to send Sterling into an absolute frenzy, demanding that everything be double-checked twice over.
No, wait, 5 minutes later, the couple is back, confessing to stealing not one but two paintings, but only for like, a little bit, so they could do some backyard vodka-paint test. And they're claiming all of the paintings in the collection are fake. That's got to be the breaking point, right? We're arresting them! Never mind, we're back on their side, working with them to figure out what the hell is going on.
After a too-long day, you figure it all out (well, not you, the criminal duo does, but you're just so fed up with the case, you don't even particularly care). The curator did it and then accidentally died in pursuit, but at least you got an answer. You need a drink. You need to return to England, away from this circus, so your boss can start acting semi-normally again.
And then comes the next morning, and Sterling is trotting right back to the estate to arrest a 3rd person in the case, because even though he says he hates their guts, apparently, the second the criminal couple calls, he will come right back to them like a trained dog.