Kate Medina’s Fire Damage (HarperCollins, £12.99), the first in a series featuring Army Psychologist Dr Jessie Flynn is an absorbing and convincing thriller from an author whose armed services background adds a subtle layer of conviction to her writing. Jessie is, naturally, almost as neurotic as some of her own patients, but Medina’s convincingly tough prose and psychological insight ensure that her damaged protagonist is never less than fascinating.

Jessie is assigned to work with a young boy named Sami, who suffers from a crippling fear of the “Shadowman”. He also talks about “the girl” being afraid and frequently clams up at the idea of burnt animals and people. Jessie is asked by Sami’s parents – one of whom is an army officer – to try and cure his condition. Meanwhile, one of her former patients requires assistance in dealing with the family of a young soldier who was killed in mysterious circumstances while on tour in Afghanistan. Sure enough, the two cases soon converge, but even if Medina employs a few clichés in the structure of her novel, the confidence of her prose and her ability to present astute psychological portraits more than makes up for the occasionally familiar twist. Fire Damage feels a touch more mainstream that the author’s earlier novel from 2014, White Crocodile, but it showcases the same talent and authenticity, confirming Medina as an author who consistently delivers taut, believable and unsettlingly compelling novels.

Less believable is Fiona Barton’s hotly hyped psychological suspense debut, The Widow (Transworld, £12.99). Jean Taylor’s husband Glen has been accused of the abduction and murder of a young girl. Despite all the evidence Jean stands by her man, but after his death, she decides finally to tell the truth about what happened and the reality of their life together.

There is ample opportunity for such a premise to create a novel of depth and subtlety, but sadly, veteran journalist Fiona Barton opts for a predictable and well-worn path of least resistance. There are a few potentially interesting scenes and a couple of moments where you wonder if Jean is smarter than she’s letting on, but mostly the book lumbers onward with a lack of focus as it jumps between hackneyed scenes of Jean’s confession, a superfluous story of a journalist looking to learn the truth, and the by-the-book police investigation into the missing girl.

The novel promises to let us into the mind of those who stand by and support their apparently monstrous loved ones. But there are no unexpected or unusual insights, and Jean seems, at times, wilfully ignorant, acting simply in order to preserve the final surprise. Perhaps some of this comes from Barton’s experience covering similar real-life stories, but unfortunately Jean is propped up by a clichéd supporting cast and a final twist that feels less of a surprise and more of a moral cop-out. Of course, many readers don’t necessarily want to be surprised or challenged, and The Widow will likely fly off the shelves on its enticing premise alone. But if you’re looking for subtlety of character, plot or theme you won’t find them here.

For those seeking a more complex and morally ambiguous read, Tim Baker’s Fever City (Faber & Faber, £12.99) might be worth a look. An ambitious conspiracy thriller that spans decades, it follows the lead of classics such as Don Delilo’s Libra and James Ellroy’s American Tabloid, and while it is exhausting, this rewarding tale sheds new light on the Kennedy assassination.

In 2014, the son of private investigator Nick Alston stumbles across research that links his father to the events in Dallas of 1963 and the mysterious case of an abducted child. Soon, he realises that his father’s most famous investigation may reveal the truth about what really happened that day. The book follows Nick’s initial investigation in 1960, his son’s own detective work in 2014, and the story of a mob hitman named Hastings in 1963-4. This is a novel that requires patience and concentration to connect the three strands, but the effort is worthwhile.

Baker’s prose is tight and evocative. He occasionally hits an Ellroy-esque rhythm, but never descends into parody. His style may be similar, but his voice is his own. The conclusions reached aren’t ground-breaking, but the story’s focus on the personal effects of the conspiracy on his cast makes for a gripping read. Where he differs from the authors that precede him in the JFK-assassination field is in his absolute dedication to making this mystery about his characters rather than the political implications; something that becomes very clear in the book’s final third, as the tension ratchets, and the sense of dreadful inevitability becomes inescapable.