Ageing, gravely ill, physicist Dronov is engaged in the development of a space engine, when his doctor orders htm to stop working. He hands over the direction of his experiments to his favourite pupil, Vyazmin, who, however, hasn't the stature to cope with the irresponsible egotism of the director of the laboratory. When accidents occur, they are glossed over to keep the research establishment's reputation intact. Vyazmin — in love with scientist Rumantseva, who, in turn, admires and loves Dronov — gets into serious trouble when the accidents are discovered and it is disclosed thai he helped in their covering up. Dronov has to come out of retirement to restore order and put the continuation of his research plans into safe hands.

The film is derived from a successful stage play based on the figure of a famous scientist, and in both cases Tcherkasov played the leading role. In modern guise, Tcherkasov brings splendid authority to the portrait of the humane and completely engaged scientist, infuses his role with warmth and a continuous sparkle of humour.

All the other roles are well acted and the direction is wholesome along classical Russian lines. The interest of the film is greatly enhanced by the script in which hitherto untouched and delicate subjects are handled with tact and lack of overemphasis; for the first time we sec a filmed admission that things can go wrong even in Soviet atomic research. There is an authentic and detailed presentation of the household of an eminent Russian scientist, complete with jealous wife, circle of friends, servant etc. A discussion between Dronov and his brother-in-law, who is a priest, lacks all elements of the sort of caricature which characterised the por­trayal of the clergy in earlier Soviet films, and even though the physicist wins the argument, the figure of the priest is treated with respect.

Perhaps the most effective scene of the film is Tcherkasov's last speech, full of fire and idealism, yet utterly underplayed. Tcherkasov gives us a completely convincing figure of the great dying scientist. The old lion hasn't lost any of his skill.