Previously, and satisfactory, adapted by London Weekend Television (later ITV) with Francesca Annis (Polanski's MACBETH) and James Warwick (NIGHTMARE MAN), the cases of Agatha Christie's "The Young Adventurers" Tommy and Tuppence Beresford are the lesser-adapted of the author's sleuths (with ITV having resurrected Miss Marple in three incarnations in order of good to downright awful and Poirot from fantastic to dire) apart from the one of the better later Marple episodes which shoehorned her into an adaptation of the Tommy and Tuppence novel By the Pricking of My Thumbs. With the latest Marple series having run its course and Poirot series reaching its bitter end, the BBC has taken a stab at Tommy and Tuppence and unfortunately taken the same sort of liberties as the later Marple entries in updating the time period and replacing wit with forced quirkiness. That said, those who either like the later Marples and Poirots - or at least find them bearable - may find this take on Partners in Crime diverting.

In the novel and previous adaptation of The Secret Adversary, young demobbed soldier Tommy Beresford and ex war volunteer Tuppence Cowley out of work and short of funds in 1919 London. Putting an advertisement in the newspaper hiring themselves out for adventure, they become embroiled in the case of a missing young woman that turns out to be part of a deeper and deadlier mystery with political ramifications. The Tommy (David Walliams, STARDUST) and Tuppence (Jessica Raine, THE WOMAN IN BLACK) of BBC's new series are a middle-aged (well, he is, at least) suburban married couple in fifties London (Tommy's military service amounting to getting run over by a catering truck upon arrival). On the train back from France with a queen bee for Tommy's latest get-rich-quick scheme of beekeeping and honey-making, Tommy and long-suffering Tuppence make the acquaintance of frightened Jane Finn (Camilla Beeput, MORTDECAI) who subsequently disappears amidst sudden gunfire, leaving behind a notebook and a photograph of a young soldier with a London address written on the back. Finding an illegal betting operation in the basement of the building, Tuppence places a bet and is then approached by the sinister Whittington (Jonny Phillips, BRONSON) with the offer to take a suitcase to Paris and live it up for six weeks under the assumed name of Jane Finn. When she mentions hearing the name before, Whittington threatens her life. When Tommy goes to his MI5 uncle Carter (James Fleet, FOUR WEDDINGS AND A FUNERAL) who tells the couple that Jane Finn had on her person a tape recording that revealed the identity of Russian assassin Mr. Brown who they believe is in the country to assassinate a high-ranking figure. Carter advises them to forget about the matter until they reveal that they have already put an ad in the paper seeking information about Jane Finn, at which point he contracts them to report to him any information they receive. Answering a response to their ad, Tommy and Tuppence meet Julius Hersheimmer (Clarke Peters, NOTTING HILL) who claims to be Jane's uncle and hires them to find her. When Tommy follows Whittington to a brothel, he is mistaken for Brown's money man and a concerned prostitute (Madeline Appiah) informs him that they are holding a mysterious new girl in the basement. Meanwhile, Tuppence goes to work as secretary for soprano Rita Vandemeyer (Alice Krige, GHOST STORY), among whose admirers is attorney Peel (Andrew Havill, THE IMITATION GAME) who is also looking for Mr. Brown. Things hit too close to home when both Tommy and Tuppence have individual brushes with death, but they are forced to press on in the investigation and possibly collaborate with the enemy when their young son (Miles Roughley) is threatened.

In N or M?, Carter is dealing with a leak at headquarters and needs a nobody to receive a message from an informant named Harrison at the opera regarding the disappearance of a Manhattan Project scientist (Danny Lee Wynter) from a seaside boarding house (along a new thermonuclear bomb, and the two keys required to arm it). Naturally, Carter thinks of Tommy but orders him to keep Tuppence in the dark, which of course does not last long. When Harrison (Trevor Cooper, DROWNING BY NUMBERS) dies from an apparent heart attack (which turns out to be poisoning) in their opera box, Tommy and Tuppence try to divine the significance of a long-winded anecdote until they discover that the man and his wife managed to bribe their way into an upgrade from house seats to an opera box. When the real Harrison (Tam Williams) is run over by a truck before he can meet with them, his dying words are that there is "a spy in the house" and that his identity is either "N" or "M" (the couple differ on the letter). Carter identifies N as a particularly elusive British Soviet spy convert, and believes him to be one of the guests at boarding house. Carter sends Tommy to the boarding house posing as a bird-watching guest to ferret out the identity of N among the guests: brassy proprietress Sheila (Aoife McMahon), her maid Veronika (Pinar Ögün), Major Khan (Alyy Khan, A MIGHTY HEART), married Jungian psychotherapists the Mintons (SHINE's Robert Hands and Issy Van Randwyck), gay divorcee Mrs. Sprot (Christina Cole, THE DEATHS OF IAN STONE), brash young boarder Carl Denim (Ed Speleers, A LONELY PLACE TO DIE), and neighboring ex-officer Commander Haydock (Roy Marsden of P.D. James' Adam Dalgliesh mystery series for ITV). When Tuppence unexpectedly turns up under the guise of a divorced authoress, the couple disagreements over the identity of likely suspect are driven by personal jealousy as their different but also start to reveal their lack of faith in one another's investigative prowess.

The first episode of the series, and "The Secret Adversary" adaptation, is a bit of a slog and feels drawn out even as one is taking in all of the changes, but the momentum of the plot starts to take hold halfway into the second episode once the stakes are raised and protagonists become more concerned with survival and each other's safety over being clever (also, at this point, one can recognize that the plot is still faithful in its broad strokes to the source). Although he would be totally miscast in a more faithful characterization of the role, Walliams does wring out some suspense from his character's buffoonery and slow-wittedness that would have gotten him killed several times over if villainous characters did not suddenly and conveniently become even slower-witted so that Tommy or someone other interested character could come up with an excuse or explanation. The constant foolhardiness of Raine's Tuppence seems to be more easily forgiven by characters who either cannot see past her looks or believe that women are just naturally nosy. Albert the lift boy from the novel is reinvented as a fellow soldier Tommy shared a medical ward with turned chemistry teacher/part-time MI5 technical wiz (Matthew Steer, BASIL) who, even with one arm, is more useful and capable than Tommy. The three-part adaptation of Christie's N or M? plays better, if possibly only because the source novel may be less familiar. The comic elements are more refined (as is the balance of humor and drama within scenes), the scenes in which Tommy's and Tuppence's individual covers are almost blown are far more tense, and the pacing is improved after the first act (in which nearly two thirds of the fifty-five minute running time has passed before Tommy gets his assignment from Carter). BBC's first stab at Agatha Christie has received mixed reviews, but the network presumably has too much invested not to produce further series (presumably several single-episode cases from the short story collection Partners in Crime and two more three-parters in By the Pricking of My Thumbs and Postern of Fate) or perhaps some of the novels without series detectives (why not an umpteenth adaptation of Ten Little Indians with the original ending?)