Welcome to our Thunderbirds Deep Dives! As we surge towards International Rescue's 60th anniversary, we asked you to pick your favourite episodes of Gerry and Sylvia Anderson's classic 1965 sci-fi adventure series that should receive in-depth, analytical retrospectives. Based on your picks, we've collated a top 10 selection of Thunderbirds greatest episodes to receive a review - as voted for by you!

We're beginning our Thunderbirds Deep Dives with a special assignment for International Rescue's chief engineer...

Hiram's Heroism

Thunderbirds' final six episodes are a curious mixture of recognisable story premises, such as runaway mega-vehicles, and renewed approaches to characterisation, including Jeff and Scott's juxtaposing views as to how International Rescue ought to be run. We've previously explored the possible reasons regarding the remarkably brief run of Thunderbirds' second series, including the idea that these last six episodes from 1966 weren't intended to be packaged as a second series, but rather, an extension of its first.

That being said, enough time and behind-the-scenes changes had occurred within AP Films to justify viewing this second series as its own distinct body of work. Perhaps most notably is the refreshed focus on Lady Penelope, Parker and Brains as the break-out stars of the series. Her ladyship and her faithful chauffeur are obvious contenders for the series' most popular characters, but Brains gets a fair amount in the spotlight during this second series, actively involved in dangerous rescue operations. This focus is felt most effectively in Alias Mr. Hackenbacker.

Skythrust calling control

Alias Mr. Hackenbacker is one of two episodes from Thunderbirds' second series written by director and the series' script editor, Alan Pattillo. For such a defining creative voice in Thunderbirds, it's striking that Pattillo's scripts deviate from the series standard techno disasters. Pattillo regularly conjured up unusual dangers for International Rescue to face, such as giant alligators and secret military codes hidden within live performances of pop artists.

In Alias Mr. Hackenbacker, Pattillo turns his attention to the dangerous underworld of... fashion espionage? It's not the most sensible premise on paper, but its absurdity makes for a refreshing change of pace within the series. If anything in the world of 2065 is prone to disaster and requires the intervention of International Rescue, why shouldn't fashion shows be included in that scope?

However, viewed through the lens of AP Films' desired success for Thunderbirds to be a sustained hit, the episode's premise of a newly launched and ultra-sophisticated passenger jet experiencing trouble with its undercarriage comes with the distinct whiff of Thunderbirds running low on ideas. As director of Trapped in the Sky, we can be lenient in forgiving Pattillo recycling the core idea of Thunderbirds' much-lauded first episode. The reuse of recognisable stock footage of London International Airport's emergency vehicles from Trapped in the Sky is a giveaway as to how much inspiration Pattillo may have taken from that earlier and more significant episode. Less forgiving is the fact that the idea of a super-powered aircraft designed by Brains becoming hijacked by villainous individuals is itself eventually repurposed as the premise of Thunderbird 6.

Nevertheless, the Skythrust craft is at the heart of the episode's story, which in turn allows Brains to take centre stage. Following a disastrous crash-landing of an earlier aircraft at London International Airport, Brains develops the new Skythrust to be equipped with revolutionary yet top secret capabilities to safeguard its aerial prowess. Adding to the importance of the Skythrust's maiden flight is Lady Penelope's intervention of allowing her friend, fashion designer Francois Lemaire, to host his new fashion show abord the passenger jet in an effort to bypass saboteurs intent on stealing the secrets of his ground-breaking new fabric.    

Brains' design efforts are crucial to the episode's climactic drama of Skythrust being taken over by enemies of Francois, who won't easily be swayed by the savvy changing of the preview's location. His arrival at London International Airport to witness the maiden flight marks a sea-change in the engineer's portrayal in Thunderbirds. Appearing in blacked-out glasses behind the wheel of a sharp automobile, he is the epitome of cool, a marked departure from the absent-minded scientist from before. His characteristic stammer had all but vanished by this point in the series. Pattillo is clearly having fun with this portrayal of Brains, and indeed, his scripts often call on amusing character dynamics. Pattillo's familiarity with Thunderbirds' ensemble cast results in nearly all the main players making appearances throughout the episode, John, Grandma and Kyrano being the only ones absent. 

Brains himself however still ends up commanding a modest presence in the episode, refraining from joining the Skythrust on its eventful maiden flight. Instead, it's Ray Barrett's ecstatic performance as Francois Lemaire that threatens to steal the episode as its star character. Barrett's wildly eclectic vocal range was a gift to the making of Thunderbirds. His ability to conjure a throbbing menace as the Hood or a stoic warmth as John Tracy made him one of Thunderbirds' most talented vocal artists. Francois and Penelope's early scenes involving Penelope uncovering a variety of bugging devices in Francois' flat is pure retrofuture spy-fi giddiness, heightened by Barrett's overzealous performance.

Where Pattillo's handling of the characters is reliably enjoyable, his depiction of International Rescue's handling of the Skythrust hijacking is less satisfying. The traditional danger zone set-up of Thunderbird 1's rapid response functionality and Thunderbird 2's subsequent heavy duty provision was often diverted away from, resulting in more creative storylines scattered throughout the series. Alias Mr. Hackenbacker rather highlights Thunderbirds' shortcomings of deviating from this approach, perhaps unintentionally bringing focus on the tricky nature of balancing its many characters and vehicles.

When villains Madeline and Mason spring their hijack operation on the unsuspecting participants of the fashion preview, Thunderbirds 1 and 2 are immediately dispatched to the rescue. Thunderbird 1 quickly becomes so redundant that Pattillo's script essentially forgets Scott's involvement in the rescue operation, instead leaving everything to Virgil and Alan aboard Thunderbird 2. Scott isn't even permitted to travel to Madeline and Mason's envisioned rendezvous point in the Sahara to meet with their fellow conspirators and violently put them out of action, something surely better suited to the fast-moving TB1.

The revelation of what exactly Brain has equipped the Skythrust with, an ejectable fuel pod, isn't the most enthralling twist, but it does allow for a sense of progression in the depiction of technology in Thunderbirds' world. Where the Fireflash had to be brought in by International Rescue's fantastic machinery, Alias Mr. Hackenbacker depicts a more self-contained style of London International Airport dealing with emergencies its own way. Unbeknown to them, the influence of International Rescue is still apparent in Skythrust's capabilities.

"1993 - the best year for champagne!"

Even with its curious drawbacks, Alias Mr. Hackenbacker remains a light-heartedly entertaining affair that throws a mildly novel spin on Thunderbirds' rescue operations. It's not one of the series' most intensely heavy duty episodes, but it's also not overly seriousness. Plenty of other episode deal in heavier topics, justifying this particular episode to let loose with amusing character dynamics and offbeat premises. The fashion preview itself doesn't skip on the series' marvellous costume designs, but the novelty could have been taken a stretch further had Brains been aboard the maiden flight and been a more proactive presence in the craft's takeover.

The episode itself also has an unexpected afterlife. Francois' revolutionary new fabric, Pennylon, would later appear in the 1968 Lady Penelope annual. more substantially, Peter Hewitt and Karey Kirkpatrick included the Skythrust in their script for Polygram and Working Title's attempts at a live-action Thunderbirds movie in the late 1990s, which would eventually evolve into the maligned 2004 film.

The reuse of the central jeopardy from Trapped in the Sky can either be taken as a shameless reuse of the same barely changed idea or a reminder of the evergreen dangers of airflight in the world of 2065. With its blend of imaginative aircraft design, reliably spectacular special effects in depicting crash-landings, and welcome dollops of wit and style, Alias Mr. Hackenbacker is a perfectly enjoyable outing that just falls shy of being a stone-cold classic of Thunderbirds' twilight episodes.

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