Bradley Hardacre has risen from poverty to become the wealthy owner of mine, mill and munitions works in Utterly. The Fairchild family live in a poor home, so what is their connection to Bradley and why does he wants to destroy the Cottage Hospital?

Austin gets a nasty shock when he walks into his new office. Matthew is excited at the thought of going to Cambridge with Morris and tells his father whilst he is visiting him in the Cottage Hospital; however, he sees Charlotte Hardacre there and the attraction continues, which in turn upsets Morris, who gains revenge by changing Matt's job.

Agnes encourages the now-hungry strikers, whilst Charlotte is 'doing good' at the soup kitchen. As Bradley makes sure George can leave the hospital (to use him for the SBD experiments), Jack and Isobel are again found in the stables, and Agnes discovers that Matt has lost his good job and is now digging coal. She then sees her husband George being driven in Bradley's car: a blackleg!

Lady Patience tells Bradley that his daughter is carrying on with a miner. Agnes informs George that the person Isobel is carrying on with is their son Jack. Bradley agrees to talk to the strikers and offers them a silent hooter — the strike is ended. George tests Bradley's anti-tank boot which explodes, and Bradley manages a pit disaster, in which he knows Jack is involved.

As Agnes and other women awaiting news of the trapped miners, the miners themselves are settling to life underground. Bradley hears that his plans are astray as Charlotte reaches the miners, but though they manage to escape as Jack supports the roof, Austin tricks Jack into shaking hands and the roof collapses.

With Jack unconscious in hospital, Bradley orders Austin to continue with the tunnel, until he reaches the Cottage Hospital, and then let off SBD (Silent But Deadly) to finish him off. Agnes and Isobel fight over Jack but he wakes up besotted with Charlotte.

George is home from hospital and Agnes tells him that Matt has gone to kill his father, Bradley, so they both go to the hall to inform Bradley. However, Austin has gone one further: he knocks Bradley out and orders him to be taken to hospital, due to be blown up at midnight with the deadly SBD.

Austin celebrates Bradley's demise, unaware that Bradley has in fact bought himself out of hospital, only to find that George hasn't caused the hospital to blow up by putting the SBD in his tea. Meanwhile, Charlotte and Morris discover Matt in bed with Lady Patience, whilst Bradley and Austin try to wrangle the truth from George as to what happened to the SBD, only to discover that George is a walking bomb.

Morris, ashamed at Lady Prudence's affair with Matt, decides to shoot himself but instead takes it out on Hesketh, his bear. Bradley and Austin discuss the fate of George and the SBD sugar lumps. McDuff uses a stomach pump to get the SBD from George but instead discovers lots of strange things George has been swallowing.

Jack proposes Bradley to sell Isobel off. Bradley agrees but Lady Patience informs him that he'd lost interest in her anyway. Lady Patience tells Matt should he continue to see her, she'll have his poems published in her name. Isobel implores Charlotte to sleep with Jack so that he will lose interest. Austin, McDuff and George experiment with the bouncing bomb, with disastrous results.

Everyone's angry with everyone! Bradley with Jack over the forge; Agnes with Jack, again for buying the forge; Isobel also with Jack when Bradley tells her she was sold to him; and Lady Patience when Morris tells her he's taking Matt to Cambridge. Morris appears to Matt in a dress and tells him he is a transvestite, successfully scaring him off.

Bradley reluctantly agrees to using Jack's truss ranges to hold up the chimney, Big Tom. Guy arrives to help Morris, who is upset because Matt doesn't fancy him. They discuss plans to blow up the Prince with SBD. McDuff tells Lady Patience that hypnotism will help her to regain the use of her legs, but it backfires. She walks away and kicks Bradley to prove it.

Bradley and Austin lecture peasants on proper behaviour for the Prince's visit. Lady Patience gives Agnes a book of Matt's poems published under her name. Matt discovers it and attempts suicide atop the big chimney.