Vila was a firm favourite with most viewers from an early time in the series, snaffling up funny lines which meshed perfectly with Michael Keating's sense of timing and the character being just the right amount of pathetic. However, in the first two seasons he didn't actually get a huge amount to do apart from make up the numbers and be the comic relief, especially as there haven't been as many locks to pick recently. However, Season 3 opted to rotate the 'lead' around a bit more than previous seasons and "City at the Edge of the World" - semi-famously devised after Keating relayed his daughter's unimpressed reaction to Vila back to Chris Boucher, who writes his first episode of the year - is Vila's day in the sun.
Often this sort of thing - putting a fun supporting character in the spotlight - can be an unsatisfying exercise but this one does the job nicely. It doesn't make the mistake of just whacking him up doing stand-up but instead plays very much to his skills - his reputation is enough for Bayban to go to considerable effort to locate and hire him while he really get to show off his skills with cracking the vault. Vila gets to be funny but not too funny and just about heroic enough to stop the thing turning into some woobie loser-fest.
The episode is also the first to really show how tense the atmosphere onboard the ship is as Tarrant bullies Vila into teleporting down to fulfil a deal Tarrant had negotiated. Cally and Avon clearly disapprove but not enough to actually step in; Avon especially only approaches it from an angle that Vila - as a good thief - is harder to replace than a pilot like Tarrant. While I doubt either of them outright despise Vila these are clearly people on the brink of a flare-up, with Vila more of a token to squabble over - you could easily see Avon intimidating Vila into something if it suited his end with Tarrant likely to take the opposing side out of sheer habit. Avon also clearly knows there's going to be some sort of a reckoning with Tarrant at some point over the newcomer's self-appointed leadership role, so perhaps by playing down what has in the past been shown as some sort of friendship with Vila he's just keeping his cards close to his chest.
After the apparently simple natives (met before by Tarrant; what, did he bump into one of them down the pub?) turn out to be a front for a more sinister group of raiders there are recriminations all around, this time with Dayna now joining in. It's almost like they don't care much for Vila but would love to take Tarrant down a peg. Interesting how he seems to have been expecting support from Dayna, too - rookies sticking together maybe, but Tarrant seems to want it both ways. He's a crap politician but to be fair does own up belatedly to being a dick about it - Steven Pacey can actually do a really good "oh shit" look when someone finally gets through to him how dumb his actions are. Which is handy, because Tarrant will do a lot of dumb stuff. While the crew have always been shown to have their disagreements his showing here is probably the nastiest one of them is to the other in the whole show; even some of Avon's later moments are at least driven by practicality and paranoia rather than simple threats.
The space pirates are led by Bayban, played by future Doctor Colin Baker. He gives a rather broad performance but it's actually very good fun, the right kind of larger-than-life menace for a story that broadly seems funny but has a bitter undertone. To be fair to Baker most of it's there in the script - his brilliant dislike of Blake using "political shortcuts" to get to the top of the Federation's most wanted list, for example - he just goes with it. Same time he might have been a good fit for Jarvik. Considering B7 has plenty of ham where it shouldn't be someone playing a space pirate with an earring over the top isn't much of a problem, David Daker is good as hapless witless lieutenant Sherm too, while Valentine Dyall is actually a good choice for the native Keezarn leader Norl. It might seem a waste to have him mainly silent but it does mean when he talks it carries a great deal of gravitas.
The other guest star is of course Carol Hawkins (formerly of the Carry On series) as Kerrill, Vila's love interest. She's actually not a bad match seeing as Bayban's crew are clearly a bunch of oddballs anyway and she just about pulls off the predictable hate-to-love relationship with Vila. She's not too glamorous either, though would it be harsh to say Boucher really shouldn't write lines about how nice Kerrill's legs are if there's a chance someone without nice legs will get the role? It's played very well for the most part considering there's never any real question of Vila leaving the Liberator, and he admits it even before Bayban's actions take it out of his hands anyway. Or is it? As well as being a world-class thief Vila is a total coward and maybe he's afraid to actually take the plunge of leaving the Liberator, where he knows what he's doing even if he's usually trying to get out of it and has Tarrant being a bastard to him the whole time. He's much more comfortable offering jokes than seriously contemplating the challenge of a new life on Gazarn with the Kerrill and citing that thieving is in his blood is a cop-out.
Worthy of particular praise is the ending when Tarrant offers apologies and some reaffirmation towards Vila, who simply brushes him off when many other shows would have a handshake and reconciliation. There's no blow out or anything, he simply doesn't care what Tarrant thinks of him either way; he breaks into things because he's good at it, not to gain admiration from the bigger boys. Nothing's really changed for the character; Tarrant's stated respect for him is probably genuine as Tarrant basically isn't smart enough to lie but it will also only last until the next time Vila does something he disapproves of. Get Orac piling in as well, though. Production is solid as well; for once the space pirate types actually look a bit like toughs and while paradise looks a bit underwhelming this is B7 after all.
The actual mystery element of the script is fairly well constructed too, with a couple of novel ideas and a fairly good explanation for the expert safecracker showing up to open the door at the right time - or at least a good enough one to pass muster for a low-key episode. So yeah, some good crew interactions, a decent lead for Vila, some fine lines, a great villain and a fun plot adds up to a highly enjoyable episode.