No, No, Not Rogov! by Cordwainer Smith

No, No, Not Rogov! by Cordwainer Smith (If, February 1959) is supposedly one of his ‘Instrumentality of Mankind’ stories, although the connection seems to be limited to a brief prologue where a golden dancer performs some sort of rapturous dance in the year AD 13,582. The bulk of the story, however, concerns itself with two Soviet scientists who are undertaking a highly secret project to develop a telepathic helmet. The pair are a married couple, Rogov (the husband) and Cherpas (the wife), who have two minders, Gausgofer (a woman who is in love with Rogov) and Gauck (a constantly expressionless man).
Their work takes place during the reigns of Stalin and Khrushchev, and they have early success in using the device to see through other people’s eyes, although the pair are never entirely sure who they are looking through or where they are. The experiment comes close to a conclusion when Rogov has a needle inserted into the top of his own head to get direct access to his optic nerve (Gauck ordering the execution of the prisoners they experiment on after a week of use has hitherto limited what they can achieve). Of course (spoiler), when the machine is connected and switched on, we see that the device operates through time as well as space, and Rogov sees the dancer in the future and goes mad:

He became blind to the sight of Cherpas, Gausgofer, and Gauck. He forgot the village of Ya. Ch. He forgot himself. He was like a fish, bred in stale fresh water, which is thrown for the first time into a living stream. He was like an insect emerging from the chrysalis. His twentieth-century mind could not hold the imagery and the impact of the music and the dance.
But the needle was there and the needle transmitted into his mind more than his mind could stand.
The synapses of his brain flicked like switches. The future flooded into him.
He fainted.
Cherpas leaped forward and lifted the needle. Rogov fell out of the chair.  p. 61 (The Year’s Best SF #5, edited by Judith Merril, 1961)

Rogov is subsequently examined by doctors but cannot be roused, nor is he later when a deputy minister from Moscow arrives with more experts. Gausgofer suggests repeating the experiment to see if she can learn something that will help recover Rogov, but is similarly affected—and she also stands up at the moment of contact, altering the needle’s position in her brain which kills her. Cherpas subsequently tells the minister that she eavesdropped on Rogov’s connection using the old equipment, and that her husband saw something unbelievably hypnotic in the far future.
The story concludes with Gauck telling the minister that the experiment is over (which I didn’t find entirely convincing, i.e. a functionary telling a Soviet deputy minister what to do).
There is probably a reasonable mainstream story about Soviet era scientists and secret police buried in this piece, but the SF parts seem like an afterthought, and the idea of someone going mad because they watch the AD 13,582 version of Strictly Come Dancing seems rather fanciful.
** (Average). 6,500 words.