Colin and Zoe are preparing their wedding day. Bayleaf goes to Spain and yells at the lazy, sunbathing private eye to help him find Melanie. Two crooks fiddle with some electric gadgets in a hotel room, causing a huge explosion and a big crash on the street. Colin finds the remains of the electric gear in the hotel room and takes them outside. Meanwhile Sicknote realizes that the walls start crumbling and shouts at everyone to quickly leave the hotel. A helpful policeman tells Colin that he is in fact holding a bomb and orders him to stand very still. Colin is scared stiff and shaking too much to put the bomb down safely. Nick has to help him. An expert later explains that the bomb wasn't sharp yet and nothing could have happened, so Colin wet himself for nothing. Bayleaf finally sees Melanie, who's being used as a servant girl in a cafe. She manages to steal away and he tells her to quickly fetch her passport and return. They manage to escape and he takes her home to England. Colin refuses to tell the others where he and Zoe plan to spend their wedding night to avoid having a prank played on them. On his stag night, Sicknote tries his skills at Karaoke. Kate meanwhile decides to give Ian a chance despite losing his baby and invites him to Colin's wedding. The lads tie a totally drunk Colin to a lamp post in the pouring rain until he tells them the hotel's name. Zoe makes a wonderful appearance at the church in an ancient fire engine, while Blue Watch have donned their parade uniforms. The wedding is only disturbed by the loud wailing of Colin's Mom. When Zoe throws the bridal bouquet Ian catches it, making Kate blush. George, Recall, Sicknote and Kevin come to the Clarendon hotel, asking for the Parrish's. But only a couple named Smith have booked in for the night. Suspecting a fake name, the guys barge into the hotel room with a lot of noise, scaring the living daylights out of the poor couple in the room - who are strangers indeed. Colin and Zoe are meanwhile enjoying an undisturbed wedding night at the Tower Thistle hotel. During the next duty, Nick hands over a postcard from Colin, explaining the hoax. The series ends with a threat of Blackwall being closed and Hallam making a passionate speech to save the fire station.

Kelly and George enjoying some domestic happiness with their baby Sean, Recall and Laura are relieved when Jamie can leave the hospital after the successful transplantations. A burglar trying to enter a wine store in "mission impossible" manner slips, and is left dangling in mid-air for the rest of the night. Hallam, Recall and Bayleaf engineer a prank on Colin writing a fake memo with juicy contents he is to copy for the area command headquarters. Over-zealous Colin hands the memo to the brigade mailman who takes it away before Hallam can stop him. He and Bayleaf bicker about the prank gone wrong, blaming each other, until Nick almost catches them out. The private eye tells Bayleaf and Claire that he has found Melanie. Sicknote comes home to find Cynthia with Jean, "making friends" - when they get a minute on their own, he tells her to leave him alone. Kate tells Ian that she has decided not to keep the baby in order to continue her career at the fire brigade. ACO Bulstrode sees Nick about the odd memo, but while he can take a joke and laugh about the prank, Nick is furious. Colin hears from another fireman who brings fresh oxygen bottle that he has been on the butt end of the watch's practical jokes once more and is upset. Kevin goes on his survival training. He is pleased to see Marion coming to visit him at the hotel, but she has only come to tell him it's over. Having lost Vaseline years ago, she couldn't bear the thought of losing another firefighting boyfriend, so she quits. A huge gas-filled pig explodes in a nightclub, causing a big fire and panic among the young clubbers. As the crowd tries to get out of the burning building, Kate is knocked to the ground and trampled on. Back at the fire station she realizes that she has lost the baby.

Blue Watch is still playing basketball and Nick brings them their own team shirts - "Blackwall Blaze". Hallam tries to teach tactics, but the guys prefer chatting. Crooks throw a molotov cocktail into a pub, which goes on fire. Upstairs, people are trapped in their flats. Hallam has a hard time to save himself by lifting himself up through a window in the ceiling, dropping his BA and helmet despite the smoke to be lighter. Blackwall Blaze is ready for their first Basketball match, but the opponents turn out to be a lot taller - and better. Colin gets knocked on his nose and drops out, so that coach Hallam has to join himself, but to no avail. Blue Watch suffers a miserable defeat. Hallam suggests to go boozing in a strip club to cheer themselves up, but the club has been closed and the pier is deserted. The mood is as gloomy as the weather, just when they see a girl about to jump into the sea from the pier. Recall and Hallam heroically jump into the sea after her to save her - their day out turns into another rescue operation. In the end, they find an open pub, where they get drinks and flirt with women. Hallam, Sicknote and Bayleaf, racked by private problems are glum and get drunk. Jaffa first urges them to go home, but loses his mind over a woman and is later found in their camper with his trousers down. Bayleaf cries about Melanie on Sicknote's shoulder. Colin is so drunk that he has the courage to phone Zoe in London and propose to her - while the other guys laugh themselves silly. Zoe, who's with Kelly, is beside herself with joy. Hallam's blissful memories of their night out are shattered when Sandra finds a picture of the "firemen heros" in the morning paper - showing them surrounded by women.

Colin has once more chickened out, much to Zoe's dismay, while everyone teases him at the station. Nick tells Kevin that he has been accepted for a course in survival training. Then Blue Watch is called to free a man whose Houdini act has gone wrong. Kevin and Marion have a row about the course he wants to attend, leaving her behind. Bayleaf and Claire hire a private investigator to find Melanie in Spain. Jamie is in hospital to have a lung and heart transplantation and Hallam and Sandra come to visit Recall and Laura. Ian talks Kate into keeping the baby instead of having an abortion. Blue Watch starts training for a charity basketball match. Colin accidentally knocks Hallam out, who continues in a filthy mood for the rest of the day. Nick hears about Bayleaf's problem to raise the cash for the private eye and gives him a cheque from the brigade. An elderly worker on the Thames Barrier has suffered an heart attack. Firemen and paramedics have a hard time to get him out of the bowels of the huge barrier and lift him up. Meanwhile Kelly has contractions and is taken to hospital. On returning to the station from the barrier, Maggie tells George that she has called and he rushes off at once. At the hospital, Kelly finally rebels against her dominating mother and is re-united with George. The whole watch comes to congratulate them after the shift. Colin finally moves in with Zoe.

An illegal garage where stolen cars are changed and get new colours goes on fire with a guy trapped inside. Kate has gone to see her doctor and arrives late for duty, missing the firemen who are just rushing off to the garage fire. A hose gets tangled up and George pulls at it, causing a shelf to collapse and bury Kevin beneath. He is freed, but the trapped guy gets fried. Sicknote goes to visit Cynthia at home. Helen complains about Malcolm choosing the brigade first. Kelly secretly hopes that George will come and take her home, but her mother sends her to her room like a little child and tells George on the front door to get lost. Zoe is furious that Colin still hasn't talked to his Mom about moving out. In the end, both Colin and George are forgiven. Sicknote and Cynthia start rehearsing and end kissing in earnest. After Kate's refusal to get in touch with Ian, her flatmate Mary interferes and goes to talk to him. Kate is NOT happy when she comes home to find him on the couch, knowing about her pregnancy. Bayleaf receives a postcard from Melanie, confirming that she has been taken to Spain by her mother. Malcolm has gone to lead an ancient bloke around the brigade museum and listens to his tales. It makes him decide to quit the brigade and go to Brussels with Helen, choosing her above his job. The others all say goodbye.

Nick is invited to a posh dinner at the chamber of commerce, but instead of praising them, he holds a furious speech about unsafe cars and reckless driving, recalling the huge accident they had encountered in very graphic details - the hosts are not pleased. Kate is at a boozy party where a young cop chats her up. George and Kelly suffer from Beattie's many noisy kids, while Malcolm has a furious row with Helen at a pub, when he refuses to go to Brussels with her. He pleads with someone in the ladies' but it turns out that it was not Helen who was inside... Bayleaf learns from Karen's mother that they have gone to Spain with Melanie. Kate ends up in bed with Ian, but wakes up full of regrets in the morning. Blue Watch is called to a house fire in the living room, where the stereo has caught fire. Colin rescues the fish who were on dry land after the aquarium burst and puts them into another aquarium without thinking. The little girl who owns the fish gets the shock of her lifetime when she sees her fishies having been butchered by the piranhas who live in the other aquarium... Kelly is fed up with Beattie's kids and askes George to throw them out again. When he refuses, SHE moves out and back in with her own parents. Doctors suggest transplantation for Jamie to Recall and Laura. Nick finds that he has m ade the local headlines with his furious speech against the motor trade. He gets a grilling from ACO Bulstrode and goes to see the widow of the man who had died in the crash. Her grief makes him crumble at last. Jean is fuming with jealousy when Sicknote and Cynthia kiss rather too passionately during rehearsals. Zoe is happy when Colin asks her out but instead of the restaurant she expected, he takes her to a fish & chips van despite the cold weather. She asks him to move in with her, but he can't stand up to his bossy mother. Kate worries about being pregnant after her one night stand with Ian. During a shout at a burning warehouse she absent-mindedly turns off the sprinklers and endangers Kevin's and Malcolm's lives. Nick shouts at her, but she refuses t o tell anyone about her worries.

George's brother-in-law Cyril is threatened by debt collectors but Beattie doesn't get an explanation. Bayleaf goes to talk to Karen, who remains stubborn about wanting custody for Melanie. A well-dressed woman has apparently locked herself out of her house and sweet-talks Nick into breaking in for her. The men are all charmed by her, only Kate is suspicious, but nobody listens to her. Despite the lady's calls to be careful, Recall manages to destroy half of the bathroom when he climbs through the window. In the evening, a furious stranger comes to the fire station demanding to see the station officer. He yells at Nick that the "charming lady" was in fact his ex-wife whom he had tried to keep out of the house by changing the locks on the doors. Now she has run off with half of the household. Nick and the guys are speech less, while Kate enjoys herself. During rehearsals for Richard III., Jean and Cynthia continually bicker. George and Kelly are just visiting when the debt collectors appear at Beattie's place. George drives them away for the time being and offers Beattie to move in with them. Sicknote takes Cynthia home after the rehearsal and kisses her, but she runs off. On the next morning, Karen comes to Melanie's school and lures her away. At the fire station, Kevin asks Nick about a possible promotion - Nick suggests specialization somewhere. Thick fog causes an accident on the motorway and a huge pile-up. A man is trapped in his burning car. Blue Watch manage to get through to the site of the accident and Nick sees a lorry with gas bottles that could possibly explode endash and later on do. The firemen try to support the many victims, while Nick and Hallam wonder about onlookers and reckless drivers. On coming home, Bayleaf realizes that Karen has kidnapped Melanie.

Blue Watch is grumbling because they are on duty on a Sunday. A young girl has gone missing in an old warehouse and the brigade is called to find her and get her out. Kate, the slimmest one of the watch, is sent through the ventilation system and finally locates the girl stuck under debris in one of the rooms. A hole has to be cut into the outside wall to get in there and free her. Elsewhere, a young guy has cracked up after too many rows with his parents and too many computer games. He climbs up a crane. Bayleaf is sent up to talk him out of his suicide plans, but the boy stuns him by explaining that his folks "told him to". At the end of this long Sunday, the girl is freed from the warehouse, but the boy loses it completely and falls from the crane, much to Bayleaf's shock.

Blue Watch gets a videotape in the mail informing them that their mascot has been kidnapped. Instead of paying ransom they invade Borough St. Station at night and Malcolm steals the dentures of one of their firemen, with which he scares Colin to death. Next morning, the fuming but toothless fireman from Borough St. turns up with his mates, demanding his teeth back. Recall hands them over in exchange for the kidnapped plastic fireman. Nick is fuming when he hears the full story, but even when he grills his firemen in the station office, they can hardly surpress giggling. Two little kids play around in a car, setting it on fire with the smaller one trapped inside. Although Blue Watch can put out the blaze, the poor kid is fried. POP's is auditioning for "Richard III". After securing the male lead for himself, Sicknote casts a newcomer named Cynthia as his partner, leaving Jean fuming with jealousy. Colin learns that he may stay in the fire brigade despite his earlier bungles. Nick is in court about a bungle and faulty orders during an earlier shout (?). A guy accidentally sets the attic of his house on fire and Blue Watch is called to put it out. After the shift, Colin has a big party to celebrate his success, but his Mom is NOT pleased when she catches him and Zoe snogging.

John Hallam is off-duty to finally receive counselling after his accident in series 4. Nick, George, Kevin and Colin are checking a shopping centre for fire safety precautions. Meanwhile Claire is visited by Bayleaf's ex-wife Karen who wants to take their daughter Melanie with her, but she wants to stay with her father. Karen threatens to have Mike in court about custody. Many pumps are called to a tunnel where smoke is issueing from an unknown source - but it turns out to be a dosser frying sausages in a pan. Paul talks Jean and Sicknote into taking part in Shakespeare's Richard III, while Malcolm takes Helen out on a shopping trip and George and Colin win some goldfish on the fairground. George, Kevin and Bayleaf go to meet Recall and his family on the airport after their trip to Disneyworld in Florida. Recall has brought a plastic fireman from the States that is to serve as their mascot. When Hallam returns to duty he is stunned by the odd arrangement of a little pond and the plastic fireman in front of the fire station to cheer the place up. Instead of being amused, station officer Georgiadis is fuming and orders them to clean up. A group of young thugs cause havoc on the fun fair and crash the Big Wheel. People are left dangling in mid-air or squeezed into tiny carriages and Blue Watch is called to free them.