After a £7,000 diversion to Bristol, Carolyn forbids Martin to make any more diversions in the future. Partway to Abu Dhabi, however, Douglas realizes that, despite reminders about the cargo-hold heating, Martin has left a client's cat in the unheated hold. Martin must decide whether to divert or to let the cat freeze. Meanwhile, Arthur attempts to discover how aeroplanes fly.

A stubborn passenger refuses to extinguish his cigarette and makes Martin cry. Arthur, on a mission, accidentally gives the passenger a heart attack, forcing Martin to fly back and forth between Reykjavik and Boston in indecision. Meanwhile, Martin and Douglas play a challenging game of "Simon Says".

MJN are flying an actress, for whom Arthur has a particular fondness and Carolyn not so much, to Cremona. Martin tries in vain to impress her but instead attracts her ire when she blames him for a horde of her fans showing up at her hotel. Douglas saves Martin from her anger with a dozen black shirts.

MJN are stranded on the outskirts of the Sahara Desert. Carolyn refuses to pay a pricey bill and Martin quibbles over a firetruck. Douglas joins a Scottish team in an exciting match of topless cricket while Arthur takes some embarrassing photos.

It's the annual Birling day, where MJN flies the wealthy Mr Birling to a Six Nations rugby match. Martin resents Birling's pompous ways and doesn't understand why Douglas and Arthur toady to him so much until he realizes that Birling gives huge tips to people he likes (as much as £6,000 when his team wins). Douglas and Carolyn are at war over a bottle of expensive Talisker whisky.

The crew are on standby at Fitton, waiting for an important client to call. Carolyn tries to keep them all sober in case the client calls; when she fails, drunk Martin must act as steward and sober Arthur has to pretend to be captain. In an attempt to return a gift, Martin discovers a shocking secret about Douglas.

Carolyn and her sister haven't spoken for fifteen years so when Arthur books a fake trip to Helsinki with Carolyn's sister, her husband and her grandson, it is a little awkward. Kieran intimidates Martin and shows some exceptional karate skills, Arthur makes an imaginative cake and Douglas exchanges orchids for fishcakes.

MJN is flying an orchestra to Poland. Carolyn is left to deal with a highly paranoid passenger who requests explanations for fractionally elevated arm-rests, broken glass-salt, 'Goofy,' and poisoned cheesecake. Douglas and Martin place bets over the cheese tray including a passenger derby commentated by Arthur, and Martin reveals a shocking secret to Douglas.

Carolyn, Douglas, Martin and Arthur are sent on a Safety and Emergency Procedures course. Arthur struggles with his stupidity, Douglas struggles with his impatience with Mr Sargent and Martin struggles with a health issue, so Carolyn is forced to work hard to keep her crew from losing their jobs.

After an unsuccessful birthday treat for Douglas' daughter, Carolyn makes a bet with her pilots. However, a dodgy warning light means that Martin and Arthur must fetch the engineer in a baggage truck. Douglas scrapes €20 by washing the airfield manager's car, Carolyn relaxes on a deckchair and Arthur uses the engine exhausts to make boiling water which ends badly.

Martin discovers a secret, illegal airfield pub frequented by Douglas and other airfield staff and can't decide whether to report it, as duty requires, or to turn a blind eye, as surprisingly everyone at the pub seems to like him. Meanwhile, Carolyn tries to improve Arthur's stewarding skills.

It's Christmas aboard Gerti and Arthur is singing merrily. Carolyn is treating a yacht salesman, Mr Alyakin, on the trip to Molokaʻi, but he begins to doubt the airline's competence, while Martin and Douglas go to extravagant lengths in an attempt to make it Arthur's best Christmas ever, within seven minutes.

A Canadian passenger informs Douglas that he is not professional but Martin is, which infuriates Douglas and causes him to humiliate Martin. Arthur teaches the passengers all about bears and Douglas chases them. Carolyn and Douglas also play a game of "the travelling lemon" which ends badly when Martin has a go.

It's Birling Day again and Carolyn has put Martin in charge of ensuring Douglas doesn't steal the expensive whisky meant for their client. But when the whisky does disappear and the evidence seems to point to everyone except Douglas, Martin must become the Miss Marple of MJN Air and discover the real culprit.

Martin has a soft spot for a Scottish first officer who is travelling with MJN for the day. However, Martin gets in a muddle and it all becomes a bit awkward. Carolyn meets a captain called Herc and everyone immerses themselves in exciting games whilst Martin applies a navigation-tail light onto the back of the plane. (Note: Martin is played by Tom Goodman-Hill.)

When Martin sprains his ankle and can't complete a piano delivery for his second job, Douglas and Arthur agree to help, but forgotten addresses, missing van keys, and Arthur's game of Yellow Car make the trip much more complicated than expected. Back in Fitton, Herc and Carolyn go out for lunch and an eventful dog-walk.

MJN are filming welcome and safety demonstration videos to make the airline look more professional. When no one on the crew is able or willing to deliver the lines, Carolyn appoints an actor called Martin, making the original Martin deeply jealous and paranoid. But a little competition from Herc might convince Douglas to do the video after all.

A bird strike takes out an engine, which could lead to the end of MJN Air, so Carolyn is forced to call in her ex-husband. Douglas and Martin entertain themselves with a game of "rhyming journeys" while Arthur is sure Douglas will sort the situation out.

MJN are looking forward to their day off when Mr Birling turns up demanding to be flown to Timbuktu to watch the Rugby World Cup on television so he can prove a point to his "awful wife". Martin discovers a slight problem with the planned destination, Arthur is reading a potentially problematic book and could this be the year that Carolyn steals the whisky from Douglas?

The crew are in Ireland, where Carolyn is purchasing a birthday present for Herc, assisted by Martin. However, difficulties with heavy rain, stubborn taxi drivers, poor phone reception, angry bees and jewellery-eating geese ensue. Meanwhile, Douglas and Arthur enjoy the luxuries of an empty airport with an over-enthusiastic manager.

An incredulous crew escort the young King of Liechtenstein and Princess Theresa to England, the latter becoming fond of Martin, but encounter a misunderstanding with fuel. Meanwhile, Herc is eager to enjoy his holiday, but Carolyn refuses to return his affections.

Martin learns his mother has fallen ill, and so tries to juggle flying, his secret delivery job, and competing with his sister to care for his mother, eventually enlisting Arthur to help, but when his dominating brother Simon turns up, Martin is determined to prove himself. Meanwhile, Carolyn and Douglas challenge each other to speak in words of only one syllable.

The crew must spend the night on Gerti but are distracted by uncomplicated word games, which Arthur cannot understand, and a constant alarm requiring trips out into the snow. Martin reveals his developing relationship with a princess, and Carolyn must make a decision about Herc.

Martin goes to an interview with Swiss Airways, and must fight for a place as a professional pilot. Herc and Douglas battle for metaphorical control of the plane, and Arthur discovers he is allergic to dragon fruit.

Martin decides whether to take the job with Swiss Air, and Arthur is considering a new career himself.

The crew try to work out why Gordon is so desperate to get G-ERTI back, while Carolyn makes a big decision about Herc.