The wraith-like Peter Capaldi, the enigmatic heart and/or darkness of “Criminal Record,” proves himself again one of the screen’s more intimidating actors; awaiting his measured response to any adversarial character suggests someone spinning the cylinder on a fully loaded revolver. This is a long way from his film debut as the well-scrubbed Scottish sidekick to Peter Riegert in “Local Hero”; it’s more in line with his vitriolic spin doctor Malcolm Tucker of “In the Loop.” Mr. Capaldi also has a large fan base thanks to his tenure on the venerable “Doctor Who.” In “Criminal Record,” his character might be considered Detective Chief Inspector Who.

Mr. Capaldi’s inscrutable policeman is really not the principal focus of this production, though. That would be Cush Jumbo’s June Lenker, a relative newcomer to the Metropolitan Police whose suspicions about Mr. Capaldi’s esteemed detective Daniel Hegarty lead to no end of trouble, recriminations and revelations. But as charismatic as Lenker is, and as instinctively leery we may be of Hegarty, it is the balance created between the two characters—one a dogged idealist, the other a case-hardened veteran, both carrying no end of personal baggage—that elevates the entire eight-part series. A young black female detective suspecting older white officers of racist misconduct hardly feels like a novel premise. But a viewer not quite knowing the true character of those presumed guilty—because Mr. Capaldi is so cagey, and Hegarty’s history so complicated—converts the show into something slippery and discomfiting, like a patrol car full of red herrings.