Astrophysics: A tight duo in a trio of black holes.

The author discusses supermassive black holes (SBHs) and reflects on a study in the current issue of the periodical that is related to the discovery of a triple black hole systems and methods of finding tight binary SBH systems. Topics discussed include emission of powerful gravitational waves by SBHs, use of the technique of very long baseline interferometry (VLBI) for the creation of giant radio telescopes, and astronomical observations of active galaxies.