Synonyms of unlooked-for

1 Syllable
swift
2 Syllables
startling, abrupt, payback, sudden, chance, stunning
3 Syllables
amazing, fortuitous, prodigious, impetuous, wonderful, staggering
4 Syllables
instantaneous, impulsive, unheralded, unpredicted, accidental, astonishing, eye-opening, electrifying, unexpected, unforeseen
5 Syllables
unpredictable
6 Syllables
unanticipated