The Letkiss is a 1960s novelty dance based on the Bunny Hop from a decade earlier.
In the early 1960s, Finnish musicians composed modern arrangements of folk music for the Jenkka, a Finnish schottische. But instead of dancing the schottische, people danced a modified Bunny Hop (beginning with the left foot instead of the right).
This new genre of music was called letkajenkka ("line schottische") based on the song "Letkajenkka" by Erik Lindström (first recorded by The Adventurers). In late 1963, Rauno Lehtinen composed another letkajenkka called "Letkis." While in Finnish, this name is simply a diminutive form of "letkajenkka" ("-is" is to Finnish as "-"ito" is to Spanish), the English speaking world interpreted this as "Let's Kiss."
This inadvertently suggestive title made this otherwise obscure genre of music popular around the world, along with the modified Bunny Hop that was danced to it.
The footwork is basically the same as the Bunny Hop, except that it starts by extending the left heel instead of the right toe.
Point left heel to the side twice (1, 2), point right heel to the side twice (3, 4). Then jump straight forward with both feet (5), jump back with both feet (6), and jump forward with both feet three times (7, and, 8) [AL64, AB64, JL65, RL65, OF65, OG65, OM65, SW65]. A more exuberant version lifts the heel rather than pointing it [AB64, RD64, GJ65].
The Letkiss is most commonly described as being danced in a single file line, with your hands on the waist [AB64, RL65, OF65] or shoulders [EF65] of the dancer in front of you.
It can also be danced as a couple dance (with the Lead's hands on the Follow's waist and the Follow's hands on the Lead's shoulders) by replacing the first forward jump with a jump to the right, the backward jump with a jump to the left, and the three forward jumps with three jumps to the left that rotate you 180° clockwise in place as a couple [EF65].
Finally, the group and couple versions of the dance can be combined as follows: in a double circle with Follows facing in and Leads facing out, dance it a couple once with right-in-right hands, then pull partner into a single-file clockwise-facing circular line during the three jumps, Follows in front of Leads. After dancing it twice in a single circle, Follows triple jump to an inside circle as Leads triple jump to an outside circle to dance it as couples once again, before pulling partner into a single-file counterclockwise-facing circle to dance it twice, before returning to the original formation [EF65].