In which the inability of Rajiv Gandhi to, you know, do his job effectively results in Congress getting a pasting across North India and losing office. His defeat marked the last time that a member of The Family would hold the office of Prime Minister (though not the last time that a member of The Family would hold power). The largest opposition party was Janata Dal (i.e. broadly speaking the socialist element of the Janata Party) and it was this party that formed a government under V.P. Singh. Unfortunately while Janata Dal was much more ideologically coherent than Janata it was dominated by Big Dramatic Personalities with a propensity for Big Dramatic Fallouts and you can probably guess what happened next... anyway this was also the first election in which the BJP established itself as a major party (and quite a few of the seats they gained in Gujarat and Madhya Pradesh they have never lost) and the first in which the BSP, Shiv Sena and JMM won seats. No election in Assam (again).
Actually in terms of vote share INC led front did not do that badly in 1989. It was almost the same as INC got in 1967 when INC actually won a slight majority of seats. It actually did very well in Karnataka and AP which they did poorly in 1984. INC did poorly in Northern India mostly because of a real swing against INC AND a de facto tactical alliance between JD BJP and Left Front.
Also the JD government fell apart mostly because INC did well enough in 1989 that JD had a majority only if you add to JD seats those of BJP and Left Front. In other words JD had to please it own internal factions AND BJP AND Left Front at the same time. To break out of this JD tried to polarized the electorate along OBC vs non-OBC terms trying to become the OBC. This lead the BJP to go for a counter-polarization of Hindus vs non-Hindus. These cross pressures lead to the fall of the the JD government. Chandra Shekhar merely came in to pick up the pieces to do a deal with INC to form a government. He did not break the JD government. It was broken by BJP and Left Front already.