March 1929. Jimmy Dillon's final act leaves Selfridge shaken and Gordon struggling to hold things together. Mae leaves for Paris. Selfridge returns to the store and promotes Miss Mardle to deputy manager and his attempt to woo the suppliers backfires when the embargo is extended to Selfridge's. Gordon approaches the main shareholder Civic Assurance, and brokers a deal to save the store who agree as long as Selfridge stands down. Mr Crabb also retires. On the 20th anniversary Selfridge leaves the store to be met by Mae.

Preparations are underway for celebrating the 20th anniversary of the store opening. Harry gets special permission to run a parade down Oxford Street, but first has to contend with the suppliers' embargo for Whiteley's. Mardle struggles to cope to make sure life continues as normal for the Grove children. Meryl suggests Mardle heads back to work and a vacancy may of just opened up for her. Jimmy's accountant makes a revelation about the Whiteley's accounts. Jimmy wonders if he can borrow stock from Selfridges as he doubts the embargo been lifted. Meryl and Freddy bring the Grove family back together for a special treat. Joe Tooby of the London Herald, has found a hole in Jimmy's story and takes his allegations straight to the press.

Harry, Gordon and Jimmy are working extra hard before their purchase of Whiteley's is announced. Grove and Crabb believe that their time is up at the company and Grove readies his retirement. Meryl looks for Tilly. Crabb offers to help out with the Whiteley accounts, but soon makes a shocking discovery. Grove has a health scare and is sent home. Mae and Harry grow closer.

June 1928. Kitty Edwards leaves for her new job in New York and after seeking advice from Selfridge, Frank goes with her. Gordon Selfridge resolves a law suit between his father and press baron Lord Wynnstay. Meryl Grove pleads for Mae's black seamstress who has been given extra work only for Mr Grove to dismiss her. Selfridge's consolidation plans are put on hold when he agrees to Jimmy Dillon's scheme to buy iconic Bayswater store William Whiteley Limited. Lord Wynnstay's reporter finds a connection between Colleano, Selfridge, D'Ancona and Jimmy Dillon.

Harry is reeling after the assault on the store. D'Ancona begins piling on more pressure so Harry is really feeling the strain, especially as the store receives a ton of bad press. Harry soon realises he has to be honest about his financial affairs. Mr Grove and Miss Mardle prepare for their upcoming event. Meryl needs Tilly's help for a task. Lady Mae and Victor become closer, making Jimmy more and more jealous.

Double Trouble is been filmed on the ground floor of the store, with the whole space transformed into a movie set. Harry is delighted that a film starring the Dolly Sisters and Bumby Wallace, has got the store been the talk of London again. Mr Grove and Miss Mardle struggle with the past and future. Kitty realises something horrible. Mae reconnects with Victor.

Harry whisks a large group of journalists to Biarritz in celebration of the hugely successful launch of the Selfridge Trust. Soon the party gets out of hand with Harry announcing the purchase of a raft of new department stores. In London, the staff prepare for a visit from author AA Milne and Grove tries to live his life as normal, but is soon distracted by a blast from the past.

Harry is enjoying himself in the roaring 20s. Grove contemplates retirement. Jimmy and Harry begin a risky new business venture, leaving Gordon angry. Harry returns to work to quash retirement rumours and makes the acquaintance of Jimmy Dillon. Kitty meets Elizabeth Arden who is opening a concession stand in the store.

Harry is at his country home recovering from the incident at the Queen of Time unveiling. He realises he needs to quash any retirement rumours, so makes a speedy return to the store and deciding to open a cutting-edge technology department. Mae is annoyed that Harry wants to be involved in her first-ever fashion launch. Jimmy makes his mark.

Harry now has a daughter, Tatiana, who is the apple of his eye. Mr Grove celebrates his birthday with Mr Crabb. Miss Mardle's absence leaves a gap in Grove's life. Gordon is now married with two children, but their is tension between him and his father. Mae returns to London.